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  • &lt;%: %&gt;, HtmlEncode, IHtmlString and MvcHtmlString

    - by Shaun
    One of my colleague and friend, Robin is playing and struggling with the ASP.NET MVC 2 on a project these days while I’m struggling with a annoying client. Since it’s his first time to use ASP.NET MVC he was meetings with a lot of problem and I was very happy to share my experience to him. Yesterday he asked me when he attempted to insert a <br /> element into his page he found that the page was rendered like this which is bad. He found his <br /> was shown as a part of the string rather than creating a new line. After checked a bit in his code I found that it’s because he utilized a new ASP.NET markup supported in .NET 4.0 – “<%: %>”. If you have been using ASP.NET MVC 1 or in .NET 3.5 world it would be very common that using <%= %> to show something on the page from the backend code. But when you do it you must ensure that the string that are going to be displayed should be Html-safe, which means all the Html markups must be encoded. Otherwise this might cause an XSS (cross-site scripting) problem. So that you’d better use the code like this below to display anything on the page. In .NET 4.0 Microsoft introduced a new markup to solve this problem which is <%: %>. It will encode the content automatically so that you will no need to check and verify your code manually for the XSS issue mentioned below. But this also means that it will encode all things, include the Html element you want to be rendered. So I changed his code like this and it worked well. After helped him solved this problem and finished a spreadsheet for my boring project I considered a bit more on the <%: %>. Since it will encode all thing why it renders correctly when we use “<%: Html.TextBox(“name”) %>” to show a text box? As you know the Html.TextBox will render a “<input name="name" id="name" type="text"/>” element on the page. If <%: %> will encode everything it should not display a text box. So I dig into the source code of the MVC and found some comments in the class MvcHtmlString. 1: // In ASP.NET 4, a new syntax <%: %> is being introduced in WebForms pages, where <%: expression %> is equivalent to 2: // <%= HttpUtility.HtmlEncode(expression) %>. The intent of this is to reduce common causes of XSS vulnerabilities 3: // in WebForms pages (WebForms views in the case of MVC). This involves the addition of an interface 4: // System.Web.IHtmlString and a static method overload System.Web.HttpUtility::HtmlEncode(object). The interface 5: // definition is roughly: 6: // public interface IHtmlString { 7: // string ToHtmlString(); 8: // } 9: // And the HtmlEncode(object) logic is roughly: 10: // - If the input argument is an IHtmlString, return argument.ToHtmlString(), 11: // - Otherwise, return HtmlEncode(Convert.ToString(argument)). 12: // 13: // Unfortunately this has the effect that calling <%: Html.SomeHelper() %> in an MVC application running on .NET 4 14: // will end up encoding output that is already HTML-safe. As a result, we're changing out HTML helpers to return 15: // MvcHtmlString where appropriate. <%= Html.SomeHelper() %> will continue to work in both .NET 3.5 and .NET 4, but 16: // changing the return types to MvcHtmlString has the added benefit that <%: Html.SomeHelper() %> will also work 17: // properly in .NET 4 rather than resulting in a double-encoded output. MVC developers in .NET 4 will then be able 18: // to use the <%: %> syntax almost everywhere instead of having to remember where to use <%= %> and where to use 19: // <%: %>. This should help developers craft more secure web applications by default. 20: // 21: // To create an MvcHtmlString, use the static Create() method instead of calling the protected constructor. The comment said the encoding rule of the <%: %> would be: If the type of the content is IHtmlString it will NOT encode since the IHtmlString indicates that it’s Html-safe. Otherwise it will use HtmlEncode to encode the content. If we check the return type of the Html.TextBox method we will find that it’s MvcHtmlString, which was implemented the IHtmlString interface dynamically. That is the reason why the “<input name="name" id="name" type="text"/>” was not encoded by <%: %>. So if we want to tell ASP.NET MVC, or I should say the ASP.NET runtime that the content is Html-safe and no need, or should not be encoded we can convert the content into IHtmlString. So another resolution would be like this. Also we can create an extension method as well for better developing experience. 1: using System; 2: using System.Collections.Generic; 3: using System.Linq; 4: using System.Web; 5: using System.Web.Mvc; 6:  7: namespace ShaunXu.Blogs.IHtmlStringIssue 8: { 9: public static class Helpers 10: { 11: public static MvcHtmlString IsHtmlSafe(this string content) 12: { 13: return MvcHtmlString.Create(content); 14: } 15: } 16: } Then the view would be like this. And the page rendered correctly.         Summary In this post I explained a bit about the new markup in .NET 4.0 – <%: %> and its usage. I also explained a bit about how to control the page content, whether it should be encoded or not. We can see the ASP.NET MVC gives us more points to control the web pages.   Hope this helps, Shaun All documents and related graphics, codes are provided "AS IS" without warranty of any kind. Copyright © Shaun Ziyan Xu. This work is licensed under the Creative Commons License.

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  • adresse book with C programming, i have problem with library i think, couldn't complite my code

    - by osabri
    I've divided my code in small programm so it can be easy to excute /* ab_error.c : in case of errors following messages will be displayed */ #include "adressbook.h" static char *errormsg[] = { "", "\nNot enough space on disk", "\nCannot open file", "\nCannot read file", "\nCannot write file" }; void check(int error) { switch(error) { case 0: return; case 1: write_file(); case 2: case 3: case 4: system("cls"); fputs(errormsg[error], stderr); exit(error); } } 2nd /* ab_fileio.c : functions for file input/output */ include "adressbook.h" static char ab_file[] = "ADRESSBOOK.DAT"; //file to save the entries int read_file(void) { int error = 0; FILE *fp; ELEMENT *new_e, *last_e = NULL; DATA buffer; if( (fp = fopen(ab_file, "rb")) == NULL) return -1; //no file found while (fread(&buffer, sizeof(DATA), 1, fp) == 1) //reads one list element after another { if( (new_e = make_element()) == NULL) { error = 1; break; //not enough space } new_e->person = buffer; //copy data to new element new_e->next = NULL; if(hol.first == NULL) //list is empty? hol.first = new_e; //yes else last_e->next = new_e; //no last_e = new_e; ++hol.amount; } if( !error && !feof(fp) ) error = 3; //cannot read file fclose(fp); return error; } /-------------------------------/ int write_file(void) { int error = 0; FILE *fp; ELEMENT *p; if( (p = hol.first) == NULL) return 0; //list is empty if( (fp = fopen(ab_file, "wb")) == NULL) return 2; //cannot open while( p!= NULL) { if( fwrite(&p->person, sizeof(DATA), 1, fp) < 1) { error = 4; break; //cannot write } p = p->next; } fclose(fp); return error; } 3rd /* ab_list.c : functions to manipulate the list */ #include "adressbook.h" HOL hol = {0, NULL}; //global definition for head of list /* -------------------- */ ELEMENT *make_element(void) { return (ELEMENT *)malloc( sizeof(ELEMENT) ); } /* -------------------- */ int ins_element( DATA *newdata) { ELEMENT *new_e, *pre_p; if((new_e = make_element()) == NULL) return 1; new_e ->person = *newdata; // copy data to new element pre_p = search(new_e->person.family_name); if(pre_p == NULL) //no person in list { new_e->next = hol.first; //put it to the begin hol.first = new_e; } else { new_e->next = pre_p->next; pre_p->next = new_e; } ++hol.amount; return 0; } int erase_element( char name, char surname ) { return 0; } /* ---------------------*/ ELEMENT *search(char *name) { ELEMENT *sp, *retp; //searchpointer, returnpointer retp = NULL; sp = hol.first; while(sp != NULL && sp->person.family_name != name) { retp = sp; sp = sp->next; } return(retp); } 4th /* ab_screen.c : functions for printing information on screen */ #include "adressbook.h" #include <conio.h> #include <ctype.h> /* standard prompts for in- and output */ static char pgmname[] = "---- Oussama's Adressbook made in splendid C ----"; static char options[] = "\ 1: Enter new adress\n\n\ 2: Delete entry\n\n\ 3: Change entry\n\n\ 4: Print adress\n\n\ Esc: Exit\n\n\n\ Your choice . . .: "; static char prompt[] = "\ Name . . . .:\n\ Surname . . :\n\n\ Street . . .:\n\n\ House number:\n\n\ Postal code :\n\n\ Phone number:"; static char buttons[] = "\ <Esc> = cancel input <Backspace> = correct input\ <Return> = assume"; static char headline[] = "\ Name Surname Street House Postal code Phone number \n\ ------------------------------------------------------------------------"; static char further[] = "\ -------- continue with any key --------"; /* ---------------------------------- */ int menu(void) //show menu and read user input { int c; system ("cls"); set_cur(0,20); puts(pgmname); set_cur(6,0); printf("%s", options); while( (c = getch()) != ESC && (c < '1' || c > '4')) putch('\a'); return c; } /* ---------------------------------- */ int print_adr_book(void) //display adressbook { int line = 1; ELEMENT *p = hol.first; system("cls"); set_cur(0,20); puts(pgmname); set_cur(2,0); puts(headline); set_cur(5,0); while(p != NULL) //run through list and show entries { printf("%5d %-15s ",line, p->person.family_name); printf("%-12s %-15s ", p->person.given_name, p->person.street); printf("%-4d %-5d %-12d\n",p->person.house_number, p->person.postal_code, p->person.phone); p = p->next; if( p == NULL || ++line %16 == 1) //end of list or screen is full { set_cur(24,0); printf("%s",further); if( getch() == ESC) return 0; set_cur(5,0); scroll_up(0,5,24);//puts(headline); } } return 0; } /* -------------------------------------------*/ int make_entry(void) { char cache[50]; DATA newperson; ELEMENT *p; while(1) { system("cls"); set_cur(0,20); puts(pgmname); set_cur(6,0); puts("Please enter new data:"); set_cur(10,0); puts(prompt); set_cur(24,0); printf("%s",buttons); balken(10, 25, MAXL, ' ',0x70); //input name if(input(newperson.family_name, MAXL, ESC, CR) == ESC) return 0; balken(12,25, MAXL, ' ', 0x70); //surname if(input(newperson.given_name, MAXL, ESC, CR) == ESC) return 0; balken(14,25, 30, ' ', 0x70); //street if(input(newperson.street, 30, ESC, CR) == ESC) return 0; balken(16,25, 4, ' ',0x70); //housenumber if(input(cache, 4, ESC, CR) == ESC) return 0; newperson.house_number = atol(cache); //to string balken(18,25, 5, ' ',0x70); //postal code if(input(cache, 5, ESC, CR) == ESC) return 0; newperson.postal_code = atol(cache); //to string balken(20,25, 20, ' ',0x70); //phone number if(input(cache, 20, ESC, CR) == ESC) return 0; newperson.phone = atol(cache); //to string p = search(newperson.phone); if( p!= NULL && p->person.phone == newperson.phone) { set_cur(22,25); puts("phonenumber already exists!"); set_cur(24,0); printf("%s, further"); getch(); continue; } } } 5th /* adress_book_project.c : main program to create an adressbook */ /* copyrights by Oussama Sabri, June 2010 */ #include "adressbook.h" //project header file int main() { int rv, cmd; //return value, user command if ( (rv = read_file() ) == -1) // no data saved yet rv = make_entry(); check(rv); //prompts an error and quits program on disfunction do { switch (cmd = menu())//calls menu and gets user input back { case '1': rv = make_entry(); break; case '2': //delete entry case '3': //changes entry rv = change_entry(cmd); break; case '4': //prints adressbook on screen rv = print_adr_book(); break; case ESC: //end of program system ("cls"); rv = 0; break; } }while(cmd!= ESC); check ( write_file() ); //save adressbook return 0; } 6th /* Getcb.c --> Die Funktion getcb() liefert die naechste * * Tastatureingabe (ruft den BIOS-INT 0x16 auf). * * Return-Wert: * * ASCII-Code bzw. erweiterter Code + 256 */ /* Hinweis: Es muss ein DOS-Compiler verwendet werden. * * (z.B. der GNU-Compiler fuer DOS auf der CD) */ #include <dos.h> int getcb(void) { union REGS intregs; intregs.h.ah = 0; // Subfunktion 0: ein Zeichen // von der Tastatur lesen. int86( 0x16, &intregs, &intregs); if( intregs.h.al != 0) // Falls ASCII-Zeichen, return (intregs.h.al); // dieses zurueckgeben. else // Sonst den erweiterten return (intregs.h.ah + 0x100); // Code + 256 } 7th /* PUTCB.C --> enthaelt die Funktionen * * - putcb() * * - putcb9() * * - balken() * * - input() * * * * Es werden die Funktionen 9 und 14 des Video-Interrupts * * (ROM-BIOS-Interrupt 0x10) verwendet. * * * * Die Prototypen dieser Funktionen stehen in BIO.H */ /* Hinweis: Es muss ein DOS-Compiler verwendet werden. * * (z.B. der GNU-Compiler fuer DOS auf der CD) */ #include <dos.h> #define VIDEO_INT 0x10 /*---------------------------------------------------------------- * putcb(c) gibt das Zeichen auf der aktuellen Cursor-Position * am Bildschirm aus. Der Cursor wird versetzt. * Steuerzeichen Back-Space, CR, LF und BELL werden * ausgefuehrt. * Return-Wert: keiner */ void putcb(unsigned char c) /* Gibt das Zeichen in c auf */ { /* den Bildschirm aus. */ union REGS intregs; intregs.h.ah = 14; /* Subfunktion 14 ("Teletype") */ intregs.h.al = c; intregs.h.bl = 0xf; /* Vordergrund-Farbe im */ /* Grafik-Modus. */ int86(VIDEO_INT, &intregs, &intregs); } /*---------------------------------------------------------------- * putcb9(c,count,mode) gibt das Zeichen in c count-mal im * angegebenen Modus auf der aktuellen * Cursor-Position am Bildschirm aus. * Der Cursor wird nicht versetzt. * * Return-Wert: keiner */ void putcb9( unsigned char c, /* das Zeichen */ unsigned count, /* die Anzahl */ unsigned mode ) /* Low-Byte: das Atrribut */ { /* High-Byte: die Bildschirmseite*/ union REGS intregs; intregs.h.ah = 9; /* Subfunktion 9 des Int 0x10 */ intregs.h.al = c; intregs.x.bx = mode; intregs.x.cx = count; int86( VIDEO_INT, &intregs, &intregs); } /*---------------------------------------------------------------- * balken() positioniert den Cursor und zeichnet einen Balken, * wobei Position, L„nge, Fllzeichen und Attribut * als Argumente bergeben werden. * Der Cursor bleibt auf der ersten Position im Balken. */ void balken( unsigned int zeile, /* Start-Position */ unsigned int spalte, unsigned int laenge, /* Laenge des Balkens */ unsigned char c, /* Fuellzeichen */ unsigned int modus) /* Low-Byte: Attribut */ /* High-Byte: Bildschirmseite */ { union REGS intregs; intregs.h.ah = 2; /* Cursor auf der angegebenen */ intregs.h.dh = zeile; /* Bildschirmseite versetzen. */ intregs.h.dl = spalte; intregs.h.bh = (modus >> 8); int86(VIDEO_INT, &intregs, &intregs); putcb9(c, laenge, modus); /* Balken ausgeben. */ } /*---------------------------------------------------------------- * input() liest Zeichen von der Tastatur ein und haengt '\0' an. * Mit Backspace kann die Eingabe geloescht werden. * Das Attribut am Bildschirm bleibt erhalten. * * Argumente: 1. Zeiger auf den Eingabepuffer. * 2. Anzahl maximal einzulesender Zeichen. * 3. Die optionalen Argumente: Zeichen, mit denen die * Eingabe abgebrochen werden kann. * Diese Liste muá mit CR = '\r' enden! * Return-Wert: Das Zeichen, mit dem die Eingabe abgebrochen wurde. */ #include <stdarg.h> int getcb( void); /* Zum Lesen der Tastatur */ int input(char *puffer, int max,... ) { int c; /* aktuelles Zeichen */ int breakc; /* Abruchzeichen */ int nc = 0; /* Anzahl eingelesener Zeichen */ va_list argp; /* Zeiger auf die weiteren Arumente */ while(1) { *puffer = '\0'; va_start(argp, max); /* argp initialisieren */ c = getcb(); do /* Mit Zeichen der Abbruchliste vergleichen */ if(c == (breakc = va_arg(argp,int)) ) return(breakc); while( breakc != '\r' ); va_end( argp); if( c == '\b' && nc > 0) /* Backspace? */ { --nc; --puffer; putcb(c); putcb(' '); putcb(c); } else if( c >= 32 && c <= 255 && nc < max ) { ++nc; *puffer++ = c; putcb(c); } else if( nc == max) putcb('\7'); /* Ton ausgeben */ } } 8th /* Video.c --> Enthaelt die Funktionen * cls(), * scroll_up(), scroll_down(), * set_cur(), get_cur(), * set_screen_page(), get_screen_page() * * Die Prototypen dieser Funktionen befinden sich in BIO.H */ /* Hinweis: Es muss ein DOS-Compiler verwendet werden. * * (z.B. der GNU-Compiler fuer DOS auf der CD) */ #include <dos.h> #include "bio.h" #define VIDEO_INT 0x10 typedef unsigned char BYTE; void scroll_up( int anzahl, int anf_zeile, int end_zeile) { /* Fenster hoch rollen. */ union REGS intregs; intregs.x.ax = 0x600 + anzahl; /* Subfunktion AH = 6, */ /* AL = Anzahl Zeilen. */ intregs.x.cx = anf_zeile << 8; /* CH=anf_zeile, cl=0 */ intregs.x.dx = (end_zeile <<8) | 79; /* DH=end_zeile,DL=79 */ intregs.h.bh = 7; /* normales Attribut */ int86(VIDEO_INT, &intregs, &intregs); } void scroll_down( int anzahl, int anf_zeile, int end_zeile) { /* Fenster runter rollen. */ union REGS intregs; intregs.x.ax = 0x700 + anzahl; /* Subfunktion AH = 7, */ /* AL = Anzahl Zeilen. */ intregs.x.cx = anf_zeile << 8; /* CH=anf_zeile, cl=0 */ intregs.x.dx = (end_zeile <<8) | 79; /* DH=end_zeile,DL=79 */ intregs.h.bh = 7; /* normales Attribut */ int86(VIDEO_INT, &intregs, &intregs); } void set_cur( int zeile, int spalte) /* versetzt den Cursor */ { /* der aktuellen Bildschirmseite.*/ union REGS intregs; intregs.h.ah = 2; intregs.h.dh = (BYTE)zeile; intregs.h.dl = (BYTE)spalte; intregs.h.bh = (BYTE)get_screen_page(); int86(VIDEO_INT, &intregs, &intregs); } void get_cur(int *zeile, int *spalte) /* holt die Cursor- */ { /* Position der aktuellen Bildschirmseite.*/ union REGS intregs; intregs.h.ah = 3; intregs.h.bh = (BYTE)get_screen_page(); int86(VIDEO_INT, &intregs, &intregs); *zeile = (unsigned)intregs.h.dh; *spalte = (unsigned)intregs.h.dl; } void cls(void) { scroll_up(0,0,24); /* Gesamten Bildschirm loeschen. */ set_cur(0,0); /* Cursor in Home-Position. */ } int get_screen_page(void) /* Aktuelle Bildschirmseite holen.*/ { union REGS intregs; intregs.h.ah = 15; /* Subfunktion AH = 15: */ /* Bildschirm-Modus feststellen. */ int86(VIDEO_INT, &intregs, &intregs); return (intregs.h.bh); } void set_screen_page(int seite) /* setzt die aktive Seite des */ { /* Bildschirmpuffers auf die */ /* angegebene Seite. */ union REGS intregs; intregs.x.ax = 0x500 + seite; /* Subfunktion AH = 5 */ int86(VIDEO_INT, &intregs, &intregs); } /* ------------------------------------------------------------- Ein kleines Testprogramm : */ /* #include <stdio.h> int main() { cls(); set_cur(23, 0); printf("Weiter mit <Return>\n"); set_cur(12, 20); printf("Ein Test!\n"); getchar(); scroll_up(3, 5, 20); getchar(); scroll_down(6, 5, 20); getchar(); set_screen_page(1); printf("\nAuf der 2. Seite !\n"); getchar(); set_screen_page(0); set_cur(0,0); printf("\nWieder auf der 1. Seite !\n"); getchar(); cls(); return 0; } */ /* Video.c --> Enthaelt die Funktionen * cls(), * scroll_up(), scroll_down(), * set_cur(), get_cur(), * set_screen_page(), get_screen_page() * * Die Prototypen dieser Funktionen befinden sich in BIO.H */ /* Hinweis: Es muss ein DOS-Compiler verwendet werden. * * (z.B. der GNU-Compiler fuer DOS auf der CD) */ #include <dos.h> #include "bio.h" #define VIDEO_INT 0x10 typedef unsigned char BYTE; void scroll_up( int anzahl, int anf_zeile, int end_zeile) { /* Fenster hoch rollen. */ union REGS intregs; intregs.x.ax = 0x600 + anzahl; /* Subfunktion AH = 6, */ /* AL = Anzahl Zeilen. */ intregs.x.cx = anf_zeile << 8; /* CH=anf_zeile, cl=0 */ intregs.x.dx = (end_zeile <<8) | 79; /* DH=end_zeile,DL=79 */ intregs.h.bh = 7; /* normales Attribut */ int86(VIDEO_INT, &intregs, &intregs); } void scroll_down( int anzahl, int anf_zeile, int end_zeile) { /* Fenster runter rollen. */ union REGS intregs; intregs.x.ax = 0x700 + anzahl; /* Subfunktion AH = 7, */ /* AL = Anzahl Zeilen. */ intregs.x.cx = anf_zeile << 8; /* CH=anf_zeile, cl=0 */ intregs.x.dx = (end_zeile <<8) | 79; /* DH=end_zeile,DL=79 */ intregs.h.bh = 7; /* normales Attribut */ int86(VIDEO_INT, &intregs, &intregs); } void set_cur( int zeile, int spalte) /* versetzt den Cursor */ { /* der aktuellen Bildschirmseite.*/ union REGS intregs; intregs.h.ah = 2; intregs.h.dh = (BYTE)zeile; intregs.h.dl = (BYTE)spalte; intregs.h.bh = (BYTE)get_screen_page(); int86(VIDEO_INT, &intregs, &intregs); } void get_cur(int *zeile, int *spalte) /* holt die Cursor- */ { /* Position der aktuellen Bildschirmseite.*/ union REGS intregs; intregs.h.ah = 3; intregs.h.bh = (BYTE)get_screen_page(); int86(VIDEO_INT, &intregs, &intregs); *zeile = (unsigned)intregs.h.dh; *spalte = (unsigned)intregs.h.dl; } void cls(void) { scroll_up(0,0,24); /* Gesamten Bildschirm loeschen. */ set_cur(0,0); /* Cursor in Home-Position. */ } int get_screen_page(void) /* Aktuelle Bildschirmseite holen.*/ { union REGS intregs; intregs.h.ah = 15; /* Subfunktion AH = 15: */ /* Bildschirm-Modus feststellen. */ int86(VIDEO_INT, &intregs, &intregs); return (intregs.h.bh); } void set_screen_page(int seite) /* setzt die aktive Seite des */ { /* Bildschirmpuffers auf die */ /* angegebene Seite. */ union REGS intregs; intregs.x.ax = 0x500 + seite; /* Subfunktion AH = 5 */ int86(VIDEO_INT, &intregs, &intregs); } /* ------------------------------------------------------------- Ein kleines Testprogramm : */ /* #include <stdio.h> int main() { cls(); set_cur(23, 0); printf("Weiter mit <Return>\n"); set_cur(12, 20); printf("Ein Test!\n"); getchar(); scroll_up(3, 5, 20); getchar(); scroll_down(6, 5, 20); getchar(); set_screen_page(1); printf("\nAuf der 2. Seite !\n"); getchar(); set_screen_page(0); set_cur(0,0); printf("\nWieder auf der 1. Seite !\n"); getchar(); cls(); return 0; } */ /* BIO.H --> Enthaelt die Prototypen der BIOS-Funktionen. */ /* --- Funktionen in VIDEO.C --- */ extern void scroll_up(int anzahl, int anf_zeile,int end_zeile); extern void scroll_down(int anzahl, int anf_zeile, int end_zeile); extern void set_cur(int zeile, int spalte); extern void get_cur(int *zeile, int *spalte); extern void cls(void); extern int get_screen_page(void); extern void set_screen_page(int page); /* --- Funktionen in GETCB.C / PUTCB.C --- */ extern int getcb(void); extern void putcb(int c); extern void putcb9(int c, unsigned count, unsigned modus); extern void balken(int zeile, int spalte, int laenge, int c, unsigned modus); extern int input(char *puffer, int max,... ); need your help, can't find my mistakes:((

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  • Address book with C programming; cannot compile my code.

    - by osabri
    I've divided my code into small programs so it can be easy to excute /* ab_error.c : in case of errors following messages will be displayed */ #include "adressbook.h" static char *errormsg[] = { "", "\nNot enough space on disk", "\nCannot open file", "\nCannot read file", "\nCannot write file" }; void check(int error) { switch(error) { case 0: return; case 1: write_file(); case 2: case 3: case 4: system("cls"); fputs(errormsg[error], stderr); exit(error); } } 2nd /* ab_fileio.c : functions for file input/output */ #include "adressbook.h" static char ab_file[] = "ADRESSBOOK.DAT"; //file to save the entries int read_file(void) { int error = 0; FILE *fp; ELEMENT *new_e, *last_e = NULL; DATA buffer; if( (fp = fopen(ab_file, "rb")) == NULL) return -1; //no file found while (fread(&buffer, sizeof(DATA), 1, fp) == 1) //reads one list element after another { if( (new_e = make_element()) == NULL) { error = 1; break; //not enough space } new_e->person = buffer; //copy data to new element new_e->next = NULL; if(hol.first == NULL) //list is empty? hol.first = new_e; //yes else last_e->next = new_e; //no last_e = new_e; ++hol.amount; } if( !error && !feof(fp) ) error = 3; //cannot read file fclose(fp); return error; } /*-------------------------------*/ int write_file(void) { int error = 0; FILE *fp; ELEMENT *p; if( (p = hol.first) == NULL) return 0; //list is empty if( (fp = fopen(ab_file, "wb")) == NULL) return 2; //cannot open while( p!= NULL) { if( fwrite(&p->person, sizeof(DATA), 1, fp) < 1) { error = 4; break; //cannot write } p = p->next; } fclose(fp); return error; } 3rd /* ab_list.c : functions to manipulate the list */ #include "adressbook.h" HOL hol = {0, NULL}; //global definition for head of list /* -------------------- */ ELEMENT *make_element(void) { return (ELEMENT *)malloc( sizeof(ELEMENT) ); } /* -------------------- */ int ins_element( DATA *newdata) { ELEMENT *new_e, *pre_p; if((new_e = make_element()) == NULL) return 1; new_e ->person = *newdata; // copy data to new element pre_p = search(new_e->person.family_name); if(pre_p == NULL) //no person in list { new_e->next = hol.first; //put it to the begin hol.first = new_e; } else { new_e->next = pre_p->next; pre_p->next = new_e; } ++hol.amount; return 0; } int erase_element( char name, char surname ) { return 0; } /* ---------------------*/ ELEMENT *search(char *name) { ELEMENT *sp, *retp; //searchpointer, returnpointer retp = NULL; sp = hol.first; while(sp != NULL && sp->person.family_name != name) { retp = sp; sp = sp->next; } return(retp); } 4th /* ab_screen.c : functions for printing information on screen */ #include "adressbook.h" #include <conio.h> #include <ctype.h> /* standard prompts for in- and output */ static char pgmname[] = "---- Oussama's Adressbook made in splendid C ----"; static char options[] = "\ 1: Enter new adress\n\n\ 2: Delete entry\n\n\ 3: Change entry\n\n\ 4: Print adress\n\n\ Esc: Exit\n\n\n\ Your choice . . .: "; static char prompt[] = "\ Name . . . .:\n\ Surname . . :\n\n\ Street . . .:\n\n\ House number:\n\n\ Postal code :\n\n\ Phone number:"; static char buttons[] = "\ <Esc> = cancel input <Backspace> = correct input\ <Return> = assume"; static char headline[] = "\ Name Surname Street House Postal code Phone number \n\ ------------------------------------------------------------------------"; static char further[] = "\ -------- continue with any key --------"; /* ---------------------------------- */ int menu(void) //show menu and read user input { int c; system ("cls"); set_cur(0,20); puts(pgmname); set_cur(6,0); printf("%s", options); while( (c = getch()) != ESC && (c < '1' || c > '4')) putch('\a'); return c; } /* ---------------------------------- */ int print_adr_book(void) //display adressbook { int line = 1; ELEMENT *p = hol.first; system("cls"); set_cur(0,20); puts(pgmname); set_cur(2,0); puts(headline); set_cur(5,0); while(p != NULL) //run through list and show entries { printf("%5d %-15s ",line, p->person.family_name); printf("%-12s %-15s ", p->person.given_name, p->person.street); printf("%-4d %-5d %-12d\n",p->person.house_number, p->person.postal_code, p->person.phone); p = p->next; if( p == NULL || ++line %16 == 1) //end of list or screen is full { set_cur(24,0); printf("%s",further); if( getch() == ESC) return 0; set_cur(5,0); scroll_up(0,5,24);//puts(headline); } } return 0; } /* -------------------------------------------*/ int make_entry(void) { char cache[50]; DATA newperson; ELEMENT *p; while(1) { system("cls"); set_cur(0,20); puts(pgmname); set_cur(6,0); puts("Please enter new data:"); set_cur(10,0); puts(prompt); set_cur(24,0); printf("%s",buttons); balken(10, 25, MAXL, ' ',0x70); //input name if(input(newperson.family_name, MAXL, ESC, CR) == ESC) return 0; balken(12,25, MAXL, ' ', 0x70); //surname if(input(newperson.given_name, MAXL, ESC, CR) == ESC) return 0; balken(14,25, 30, ' ', 0x70); //street if(input(newperson.street, 30, ESC, CR) == ESC) return 0; balken(16,25, 4, ' ',0x70); //housenumber if(input(cache, 4, ESC, CR) == ESC) return 0; newperson.house_number = atol(cache); //to string balken(18,25, 5, ' ',0x70); //postal code if(input(cache, 5, ESC, CR) == ESC) return 0; newperson.postal_code = atol(cache); //to string balken(20,25, 20, ' ',0x70); //phone number if(input(cache, 20, ESC, CR) == ESC) return 0; newperson.phone = atol(cache); //to string p = search(newperson.phone); if( p!= NULL && p->person.phone == newperson.phone) { set_cur(22,25); puts("phonenumber already exists!"); set_cur(24,0); printf("%s, further"); getch(); continue; } } } 5th /* adress_book_project.c : main program to create an adressbook */ /* copyrights by Oussama Sabri, June 2010 */ #include "adressbook.h" //project header file int main() { int rv, cmd; //return value, user command if ( (rv = read_file() ) == -1) // no data saved yet rv = make_entry(); check(rv); //prompts an error and quits program on disfunction do { switch (cmd = menu())//calls menu and gets user input back { case '1': rv = make_entry(); break; case '2': //delete entry case '3': //changes entry rv = change_entry(cmd); break; case '4': //prints adressbook on screen rv = print_adr_book(); break; case ESC: //end of program system ("cls"); rv = 0; break; } }while(cmd!= ESC); check ( write_file() ); //save adressbook return 0; } 6th /* Getcb.c --> Die Funktion getcb() liefert die naechste * * Tastatureingabe (ruft den BIOS-INT 0x16 auf). * * Return-Wert: * * ASCII-Code bzw. erweiterter Code + 256 */ /* Hinweis: Es muss ein DOS-Compiler verwendet werden. * * (z.B. der GNU-Compiler fuer DOS auf der CD) */ #include <dos.h> int getcb(void) { union REGS intregs; intregs.h.ah = 0; // Subfunktion 0: ein Zeichen // von der Tastatur lesen. int86( 0x16, &intregs, &intregs); if( intregs.h.al != 0) // Falls ASCII-Zeichen, return (intregs.h.al); // dieses zurueckgeben. else // Sonst den erweiterten return (intregs.h.ah + 0x100); // Code + 256 } 7th /* PUTCB.C --> enthaelt die Funktionen * * - putcb() * * - putcb9() * * - balken() * * - input() * * * * Es werden die Funktionen 9 und 14 des Video-Interrupts * * (ROM-BIOS-Interrupt 0x10) verwendet. * * * * Die Prototypen dieser Funktionen stehen in BIO.H */ /* Hinweis: Es muss ein DOS-Compiler verwendet werden. * * (z.B. der GNU-Compiler fuer DOS auf der CD) */ #include <dos.h> #define VIDEO_INT 0x10 /*---------------------------------------------------------------- * putcb(c) gibt das Zeichen auf der aktuellen Cursor-Position * am Bildschirm aus. Der Cursor wird versetzt. * Steuerzeichen Back-Space, CR, LF und BELL werden * ausgefuehrt. * Return-Wert: keiner */ void putcb(unsigned char c) /* Gibt das Zeichen in c auf */ { /* den Bildschirm aus. */ union REGS intregs; intregs.h.ah = 14; /* Subfunktion 14 ("Teletype") */ intregs.h.al = c; intregs.h.bl = 0xf; /* Vordergrund-Farbe im */ /* Grafik-Modus. */ int86(VIDEO_INT, &intregs, &intregs); } /*---------------------------------------------------------------- * putcb9(c,count,mode) gibt das Zeichen in c count-mal im * angegebenen Modus auf der aktuellen * Cursor-Position am Bildschirm aus. * Der Cursor wird nicht versetzt. * * Return-Wert: keiner */ void putcb9( unsigned char c, /* das Zeichen */ unsigned count, /* die Anzahl */ unsigned mode ) /* Low-Byte: das Atrribut */ { /* High-Byte: die Bildschirmseite*/ union REGS intregs; intregs.h.ah = 9; /* Subfunktion 9 des Int 0x10 */ intregs.h.al = c; intregs.x.bx = mode; intregs.x.cx = count; int86( VIDEO_INT, &intregs, &intregs); } /*---------------------------------------------------------------- * balken() positioniert den Cursor und zeichnet einen Balken, * wobei Position, L„nge, Fllzeichen und Attribut * als Argumente bergeben werden. * Der Cursor bleibt auf der ersten Position im Balken. */ void balken( unsigned int zeile, /* Start-Position */ unsigned int spalte, unsigned int laenge, /* Laenge des Balkens */ unsigned char c, /* Fuellzeichen */ unsigned int modus) /* Low-Byte: Attribut */ /* High-Byte: Bildschirmseite */ { union REGS intregs; intregs.h.ah = 2; /* Cursor auf der angegebenen */ intregs.h.dh = zeile; /* Bildschirmseite versetzen. */ intregs.h.dl = spalte; intregs.h.bh = (modus >> 8); int86(VIDEO_INT, &intregs, &intregs); putcb9(c, laenge, modus); /* Balken ausgeben. */ } /*---------------------------------------------------------------- * input() liest Zeichen von der Tastatur ein und haengt '\0' an. * Mit Backspace kann die Eingabe geloescht werden. * Das Attribut am Bildschirm bleibt erhalten. * * Argumente: 1. Zeiger auf den Eingabepuffer. * 2. Anzahl maximal einzulesender Zeichen. * 3. Die optionalen Argumente: Zeichen, mit denen die * Eingabe abgebrochen werden kann. * Diese Liste muá mit CR = '\r' enden! * Return-Wert: Das Zeichen, mit dem die Eingabe abgebrochen wurde. */ #include <stdarg.h> int getcb( void); /* Zum Lesen der Tastatur */ int input(char *puffer, int max,... ) { int c; /* aktuelles Zeichen */ int breakc; /* Abruchzeichen */ int nc = 0; /* Anzahl eingelesener Zeichen */ va_list argp; /* Zeiger auf die weiteren Arumente */ while(1) { *puffer = '\0'; va_start(argp, max); /* argp initialisieren */ c = getcb(); do /* Mit Zeichen der Abbruchliste vergleichen */ if(c == (breakc = va_arg(argp,int)) ) return(breakc); while( breakc != '\r' ); va_end( argp); if( c == '\b' && nc > 0) /* Backspace? */ { --nc; --puffer; putcb(c); putcb(' '); putcb(c); } else if( c >= 32 && c <= 255 && nc < max ) { ++nc; *puffer++ = c; putcb(c); } else if( nc == max) putcb('\7'); /* Ton ausgeben */ } } 8th /* Video.c --> Enthaelt die Funktionen * cls(), * scroll_up(), scroll_down(), * set_cur(), get_cur(), * set_screen_page(), get_screen_page() * * Die Prototypen dieser Funktionen befinden sich in BIO.H */ /* Hinweis: Es muss ein DOS-Compiler verwendet werden. * * (z.B. der GNU-Compiler fuer DOS auf der CD) */ #include <dos.h> #include "bio.h" #define VIDEO_INT 0x10 typedef unsigned char BYTE; void scroll_up( int anzahl, int anf_zeile, int end_zeile) { /* Fenster hoch rollen. */ union REGS intregs; intregs.x.ax = 0x600 + anzahl; /* Subfunktion AH = 6, */ /* AL = Anzahl Zeilen. */ intregs.x.cx = anf_zeile << 8; /* CH=anf_zeile, cl=0 */ intregs.x.dx = (end_zeile <<8) | 79; /* DH=end_zeile,DL=79 */ intregs.h.bh = 7; /* normales Attribut */ int86(VIDEO_INT, &intregs, &intregs); } void scroll_down( int anzahl, int anf_zeile, int end_zeile) { /* Fenster runter rollen. */ union REGS intregs; intregs.x.ax = 0x700 + anzahl; /* Subfunktion AH = 7, */ /* AL = Anzahl Zeilen. */ intregs.x.cx = anf_zeile << 8; /* CH=anf_zeile, cl=0 */ intregs.x.dx = (end_zeile <<8) | 79; /* DH=end_zeile,DL=79 */ intregs.h.bh = 7; /* normales Attribut */ int86(VIDEO_INT, &intregs, &intregs); } void set_cur( int zeile, int spalte) /* versetzt den Cursor */ { /* der aktuellen Bildschirmseite.*/ union REGS intregs; intregs.h.ah = 2; intregs.h.dh = (BYTE)zeile; intregs.h.dl = (BYTE)spalte; intregs.h.bh = (BYTE)get_screen_page(); int86(VIDEO_INT, &intregs, &intregs); } void get_cur(int *zeile, int *spalte) /* holt die Cursor- */ { /* Position der aktuellen Bildschirmseite.*/ union REGS intregs; intregs.h.ah = 3; intregs.h.bh = (BYTE)get_screen_page(); int86(VIDEO_INT, &intregs, &intregs); *zeile = (unsigned)intregs.h.dh; *spalte = (unsigned)intregs.h.dl; } void cls(void) { scroll_up(0,0,24); /* Gesamten Bildschirm loeschen. */ set_cur(0,0); /* Cursor in Home-Position. */ } int get_screen_page(void) /* Aktuelle Bildschirmseite holen.*/ { union REGS intregs; intregs.h.ah = 15; /* Subfunktion AH = 15: */ /* Bildschirm-Modus feststellen. */ int86(VIDEO_INT, &intregs, &intregs); return (intregs.h.bh); } void set_screen_page(int seite) /* setzt die aktive Seite des */ { /* Bildschirmpuffers auf die */ /* angegebene Seite. */ union REGS intregs; intregs.x.ax = 0x500 + seite; /* Subfunktion AH = 5 */ int86(VIDEO_INT, &intregs, &intregs); } /* ------------------------------------------------------------- Ein kleines Testprogramm : */ /* #include <stdio.h> int main() { cls(); set_cur(23, 0); printf("Weiter mit <Return>\n"); set_cur(12, 20); printf("Ein Test!\n"); getchar(); scroll_up(3, 5, 20); getchar(); scroll_down(6, 5, 20); getchar(); set_screen_page(1); printf("\nAuf der 2. Seite !\n"); getchar(); set_screen_page(0); set_cur(0,0); printf("\nWieder auf der 1. Seite !\n"); getchar(); cls(); return 0; } */ /* Video.c --> Enthaelt die Funktionen * cls(), * scroll_up(), scroll_down(), * set_cur(), get_cur(), * set_screen_page(), get_screen_page() * * Die Prototypen dieser Funktionen befinden sich in BIO.H */ /* Hinweis: Es muss ein DOS-Compiler verwendet werden. * * (z.B. der GNU-Compiler fuer DOS auf der CD) */ #include <dos.h> #include "bio.h" #define VIDEO_INT 0x10 typedef unsigned char BYTE; void scroll_up( int anzahl, int anf_zeile, int end_zeile) { /* Fenster hoch rollen. */ union REGS intregs; intregs.x.ax = 0x600 + anzahl; /* Subfunktion AH = 6, */ /* AL = Anzahl Zeilen. */ intregs.x.cx = anf_zeile << 8; /* CH=anf_zeile, cl=0 */ intregs.x.dx = (end_zeile <<8) | 79; /* DH=end_zeile,DL=79 */ intregs.h.bh = 7; /* normales Attribut */ int86(VIDEO_INT, &intregs, &intregs); } void scroll_down( int anzahl, int anf_zeile, int end_zeile) { /* Fenster runter rollen. */ union REGS intregs; intregs.x.ax = 0x700 + anzahl; /* Subfunktion AH = 7, */ /* AL = Anzahl Zeilen. */ intregs.x.cx = anf_zeile << 8; /* CH=anf_zeile, cl=0 */ intregs.x.dx = (end_zeile <<8) | 79; /* DH=end_zeile,DL=79 */ intregs.h.bh = 7; /* normales Attribut */ int86(VIDEO_INT, &intregs, &intregs); } void set_cur( int zeile, int spalte) /* versetzt den Cursor */ { /* der aktuellen Bildschirmseite.*/ union REGS intregs; intregs.h.ah = 2; intregs.h.dh = (BYTE)zeile; intregs.h.dl = (BYTE)spalte; intregs.h.bh = (BYTE)get_screen_page(); int86(VIDEO_INT, &intregs, &intregs); } void get_cur(int *zeile, int *spalte) /* holt die Cursor- */ { /* Position der aktuellen Bildschirmseite.*/ union REGS intregs; intregs.h.ah = 3; intregs.h.bh = (BYTE)get_screen_page(); int86(VIDEO_INT, &intregs, &intregs); *zeile = (unsigned)intregs.h.dh; *spalte = (unsigned)intregs.h.dl; } void cls(void) { scroll_up(0,0,24); /* Gesamten Bildschirm loeschen. */ set_cur(0,0); /* Cursor in Home-Position. */ } int get_screen_page(void) /* Aktuelle Bildschirmseite holen.*/ { union REGS intregs; intregs.h.ah = 15; /* Subfunktion AH = 15: */ /* Bildschirm-Modus feststellen. */ int86(VIDEO_INT, &intregs, &intregs); return (intregs.h.bh); } void set_screen_page(int seite) /* setzt die aktive Seite des */ { /* Bildschirmpuffers auf die */ /* angegebene Seite. */ union REGS intregs; intregs.x.ax = 0x500 + seite; /* Subfunktion AH = 5 */ int86(VIDEO_INT, &intregs, &intregs); } /* ------------------------------------------------------------- Ein kleines Testprogramm : */ /* #include <stdio.h> int main() { cls(); set_cur(23, 0); printf("Weiter mit <Return>\n"); set_cur(12, 20); printf("Ein Test!\n"); getchar(); scroll_up(3, 5, 20); getchar(); scroll_down(6, 5, 20); getchar(); set_screen_page(1); printf("\nAuf der 2. Seite !\n"); getchar(); set_screen_page(0); set_cur(0,0); printf("\nWieder auf der 1. Seite !\n"); getchar(); cls(); return 0; } */ /* BIO.H --> Enthaelt die Prototypen der BIOS-Funktionen. */ /* --- Funktionen in VIDEO.C --- */ extern void scroll_up(int anzahl, int anf_zeile,int end_zeile); extern void scroll_down(int anzahl, int anf_zeile, int end_zeile); extern void set_cur(int zeile, int spalte); extern void get_cur(int *zeile, int *spalte); extern void cls(void); extern int get_screen_page(void); extern void set_screen_page(int page); /* --- Funktionen in GETCB.C / PUTCB.C --- */ extern int getcb(void); extern void putcb(int c); extern void putcb9(int c, unsigned count, unsigned modus); extern void balken(int zeile, int spalte, int laenge, int c, unsigned modus); extern int input(char *puffer, int max,... ); need your help, can't find my mistakes:((

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    - by Jon Galloway
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It's not hooked in with licensing or tracking the kind of code you write to sell you components. It is doing good things, like  syncing your Visual Studio settings between computers. More about that here. So, you don't have to, but I sure do. Overview of shiny new things in ASP.NET land There are a lot of good new things in ASP.NET. I'll list some of my favorite here, but you can read more on the ASP.NET site. One ASP.NET You've heard us talk about this for a while. The idea is that options are good, but choice can be a burden. When you start a new ASP.NET project, why should you have to make a tough decision - with long-term consequences - about how your application will work? If you want to use ASP.NET Web Forms, but have the option of adding in ASP.NET MVC later, why should that be hard? It's all ASP.NET, right? Ideally, you'd just decide that you want to use ASP.NET to build sites and services, and you could use the appropriate tools (the green blocks below) as you needed them. So, here it is. When you create a new ASP.NET application, you just create an ASP.NET application. Next, you can pick from some templates to get you started... but these are different. They're not "painful decision" templates, they're just some starting pieces. And, most importantly, you can mix and match. I can pick a "mostly" Web Forms template, but include MVC and Web API folders and core references. If you've tried to mix and match in the past, you're probably aware that it was possible, but not pleasant. ASP.NET MVC project files contained special project type GUIDs, so you'd only get controller scaffolding support in a Web Forms project if you manually edited the csproj file. Features in one stack didn't work in others. Project templates were painful choices. That's no longer the case. Hooray! I just did a demo in a presentation last week where I created a new Web Forms + MVC + Web API site, built a model, scaffolded MVC and Web API controllers with EF Code First, add data in the MVC view, viewed it in Web API, then added a GridView to the Web Forms Default.aspx page and bound it to the Model. In about 5 minutes. Sure, it's a simple example, but it's great to be able to share code and features across the whole ASP.NET family. Authentication In the past, authentication was built into the templates. So, for instance, there was an ASP.NET MVC 4 Intranet Project template which created a new ASP.NET MVC 4 application that was preconfigured for Windows Authentication. All of that authentication stuff was built into each template, so they varied between the stacks, and you couldn't reuse them. You didn't see a lot of changes to the authentication options, since they required big changes to a bunch of project templates. Now, the new project dialog includes a common authentication experience. When you hit the Change Authentication button, you get some common options that work the same way regardless of the template or reference settings you've made. These options work on all ASP.NET frameworks, and all hosting environments (IIS, IIS Express, or OWIN for self-host) The default is Individual User Accounts: This is the standard "create a local account, using username / password or OAuth" thing; however, it's all built on the new Identity system. More on that in a second. The one setting that has some configuration to it is Organizational Accounts, which lets you configure authentication using Active Directory, Windows Azure Active Directory, or Office 365. Identity There's a new identity system. We've taken the best parts of the previous ASP.NET Membership and Simple Identity systems, rolled in a lot of feedback and made big enhancements to support important developer concerns like unit testing and extensiblity. I've written long posts about ASP.NET identity, and I'll do it again. Soon. This is not that post. The short version is that I think we've finally got just the right Identity system. Some of my favorite features: There are simple, sensible defaults that work well - you can File / New / Run / Register / Login, and everything works. It supports standard username / password as well as external authentication (OAuth, etc.). It's easy to customize without having to re-implement an entire provider. It's built using pluggable pieces, rather than one large monolithic system. It's built using interfaces like IUser and IRole that allow for unit testing, dependency injection, etc. You can easily add user profile data (e.g. URL, twitter handle, birthday). You just add properties to your ApplicationUser model and they'll automatically be persisted. Complete control over how the identity data is persisted. By default, everything works with Entity Framework Code First, but it's built to support changes from small (modify the schema) to big (use another ORM, store your data in a document database or in the cloud or in XML or in the EXIF data of your desktop background or whatever). It's configured via OWIN. More on OWIN and Katana later, but the fact that it's built using OWIN means it's portable. You can find out more in the Authentication and Identity section of the ASP.NET site (and lots more content will be going up there soon). New Bootstrap based project templates The new project templates are built using Bootstrap 3. Bootstrap (formerly Twitter Bootstrap) is a front-end framework that brings a lot of nice benefits: It's responsive, so your projects will automatically scale to device width using CSS media queries. For example, menus are full size on a desktop browser, but on narrower screens you automatically get a mobile-friendly menu. The built-in Bootstrap styles make your standard page elements (headers, footers, buttons, form inputs, tables etc.) look nice and modern. Bootstrap is themeable, so you can reskin your whole site by dropping in a new Bootstrap theme. Since Bootstrap is pretty popular across the web development community, this gives you a large and rapidly growing variety of templates (free and paid) to choose from. Bootstrap also includes a lot of very useful things: components (like progress bars and badges), useful glyphicons, and some jQuery plugins for tooltips, dropdowns, carousels, etc.). Here's a look at how the responsive part works. When the page is full screen, the menu and header are optimized for a wide screen display: When I shrink the page down (this is all based on page width, not useragent sniffing) the menu turns into a nice mobile-friendly dropdown: For a quick example, I grabbed a new free theme off bootswatch.com. For simple themes, you just need to download the boostrap.css file and replace the /content/bootstrap.css file in your project. Now when I refresh the page, I've got a new theme: Scaffolding The big change in scaffolding is that it's one system that works across ASP.NET. You can create a new Empty Web project or Web Forms project and you'll get the Scaffold context menus. For release, we've got MVC 5 and Web API 2 controllers. We had a preview of Web Forms scaffolding in the preview releases, but they weren't fully baked for RTM. Look for them in a future update, expected pretty soon. This scaffolding system wasn't just changed to work across the ASP.NET frameworks, it's also built to enable future extensibility. That's not in this release, but should also hopefully be out soon. Project Readme page This is a small thing, but I really like it. When you create a new project, you get a Project_Readme.html page that's added to the root of your project and opens in the Visual Studio built-in browser. I love it. A long time ago, when you created a new project we just dumped it on you and left you scratching your head about what to do next. Not ideal. Then we started adding a bunch of Getting Started information to the new project templates. That told you what to do next, but you had to delete all of that stuff out of your website. It doesn't belong there. Not ideal. This is a simple HTML file that's not integrated into your project code at all. You can delete it if you want. But, it shows a lot of helpful links that are current for the project you just created. In the future, if we add new wacky project types, they can create readme docs with specific information on how to do appropriately wacky things. Side note: I really like that they used the internal browser in Visual Studio to show this content rather than popping open an HTML page in the default browser. I hate that. It's annoying. If you're doing that, I hope you'll stop. What if some unnamed person has 40 or 90 tabs saved in their browser session? When you pop open your "Thanks for installing my Visual Studio extension!" page, all eleventy billion tabs start up and I wish I'd never installed your thing. Be like these guys and pop stuff Visual Studio specific HTML docs in the Visual Studio browser. ASP.NET MVC 5 The biggest change with ASP.NET MVC 5 is that it's no longer a separate project type. It integrates well with the rest of ASP.NET. In addition to that and the other common features we've already looked at (Bootstrap templates, Identity, authentication), here's what's new for ASP.NET MVC. Attribute routing ASP.NET MVC now supports attribute routing, thanks to a contribution by Tim McCall, the author of http://attributerouting.net. With attribute routing you can specify your routes by annotating your actions and controllers. This supports some pretty complex, customized routing scenarios, and it allows you to keep your route information right with your controller actions if you'd like. Here's a controller that includes an action whose method name is Hiding, but I've used AttributeRouting to configure it to /spaghetti/with-nesting/where-is-waldo public class SampleController : Controller { [Route("spaghetti/with-nesting/where-is-waldo")] public string Hiding() { return "You found me!"; } } I enable that in my RouteConfig.cs, and I can use that in conjunction with my other MVC routes like this: public class RouteConfig { public static void RegisterRoutes(RouteCollection routes) { routes.IgnoreRoute("{resource}.axd/{*pathInfo}"); routes.MapMvcAttributeRoutes(); routes.MapRoute( name: "Default", url: "{controller}/{action}/{id}", defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional } ); } } You can read more about Attribute Routing in ASP.NET MVC 5 here. Filter enhancements There are two new additions to filters: Authentication Filters and Filter Overrides. Authentication filters are a new kind of filter in ASP.NET MVC that run prior to authorization filters in the ASP.NET MVC pipeline and allow you to specify authentication logic per-action, per-controller, or globally for all controllers. Authentication filters process credentials in the request and provide a corresponding principal. Authentication filters can also add authentication challenges in response to unauthorized requests. Override filters let you change which filters apply to a given action method or controller. Override filters specify a set of filter types that should not be run for a given scope (action or controller). This allows you to configure filters that apply globally but then exclude certain global filters from applying to specific actions or controllers. ASP.NET Web API 2 ASP.NET Web API 2 includes a lot of new features. Attribute Routing ASP.NET Web API supports the same attribute routing system that's in ASP.NET MVC 5. You can read more about the Attribute Routing features in Web API in this article. OAuth 2.0 ASP.NET Web API picks up OAuth 2.0 support, using security middleware running on OWIN (discussed below). This is great for features like authenticated Single Page Applications. OData Improvements ASP.NET Web API now has full OData support. That required adding in some of the most powerful operators: $select, $expand, $batch and $value. You can read more about OData operator support in this article by Mike Wasson. Lots more There's a huge list of other features, including CORS (cross-origin request sharing), IHttpActionResult, IHttpRequestContext, and more. I think the best overview is in the release notes. OWIN and Katana I've written about OWIN and Katana recently. I'm a big fan. OWIN is the Open Web Interfaces for .NET. It's a spec, like HTML or HTTP, so you can't install OWIN. The benefit of OWIN is that it's a community specification, so anyone who implements it can plug into the ASP.NET stack, either as middleware or as a host. Katana is the Microsoft implementation of OWIN. It leverages OWIN to wire up things like authentication, handlers, modules, IIS hosting, etc., so ASP.NET can host OWIN components and Katana components can run in someone else's OWIN implementation. Howard Dierking just wrote a cool article in MSDN magazine describing Katana in depth: Getting Started with the Katana Project. He had an interesting example showing an OWIN based pipeline which leveraged SignalR, ASP.NET Web API and NancyFx components in the same stack. If this kind of thing makes sense to you, that's great. If it doesn't, don't worry, but keep an eye on it. You're going to see some cool things happen as a result of ASP.NET becoming more and more pluggable. Visual Studio Web Tools Okay, this stuff's just crazy. Visual Studio has been adding some nice web dev features over the past few years, but they've really cranked it up for this release. Visual Studio is by far my favorite code editor for all web files: CSS, HTML, JavaScript, and lots of popular libraries. Stop thinking of Visual Studio as a big editor that you only use to write back-end code. Stop editing HTML and CSS in Notepad (or Sublime, Notepad++, etc.). Visual Studio starts up in under 2 seconds on a modern computer with an SSD. Misspelling HTML attributes or your CSS classes or jQuery or Angular syntax is stupid. It doesn't make you a better developer, it makes you a silly person who wastes time. Browser Link Browser Link is a real-time, two-way connection between Visual Studio and all connected browsers. It's only attached when you're running locally, in debug, but it applies to any and all connected browser, including emulators. You may have seen demos that showed the browsers refreshing based on changes in the editor, and I'll agree that's pretty cool. But it's really just the start. It's a two-way connection, and it's built for extensiblity. That means you can write extensions that push information from your running application (in IE, Chrome, a mobile emulator, etc.) back to Visual Studio. Mads and team have showed off some demonstrations where they enabled edit mode in the browser which updated the source HTML back on the browser. It's also possible to look at how the rendered HTML performs, check for compatibility issues, watch for unused CSS classes, the sky's the limit. New HTML editor The previous HTML editor had a lot of old code that didn't allow for improvements. The team rewrote the HTML editor to take advantage of the new(ish) extensibility features in Visual Studio, which then allowed them to add in all kinds of features - things like CSS Class and ID IntelliSense (so you type style="" and get a list of classes and ID's for your project), smart indent based on how your document is formatted, JavaScript reference auto-sync, etc. Here's a 3 minute tour from Mads Kristensen. The previous HTML editor had a lot of old code that didn't allow for improvements. The team rewrote the HTML editor to take advantage of the new(ish) extensibility features in Visual Studio, which then allowed them to add in all kinds of features - things like CSS Class and ID IntelliSense (so you type style="" and get a list of classes and ID's for your project), smart indent based on how your document is formatted, JavaScript reference auto-sync, etc. Lots more Visual Studio web dev features That's just a sampling - there's a ton of great features for JavaScript editing, CSS editing, publishing, and Page Inspector (which shows real-time rendering of your page inside Visual Studio). Here are some more short videos showing those features. Lots, lots more Okay, that's just a summary, and it's still quite a bit. Head on over to http://asp.net/vnext for more information, and download Visual Studio 2013 now to get started!

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  • TFS 2008 Web Access Report 100 record limitation

    - by HosamKamel
    By default TFS 2008 Web Access has the limit of 100 record when you open any query in report mode. Even if you tried to export the query to excel or PDF you will only get first 100 record exported. To overcome this issue, you have to reconfigure this count in the web.config file Navigate to web access files C:\Program Files\Microsoft Visual Studio 2008 Team System Web Access\Wiwa Open web.config modify maxWorkitemsInReportList count to whatever count you need. You need to do modify the same configuration in web.config located here C:\Program Files\Microsoft Visual Studio 2008 Team System Web Access\Web  A full discussion thread exists here Team Foundation Server - Team System Web Access

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  • Python requests SSL version

    - by Aaron Schif
    I am using the python requests module on Ubuntu 13.04. I keep getting the error: requests.exceptions.SSLError: [Errno 1] _ssl.c:504: error:14077410:SSL routines:SSL23_GET_SERVER_HELLO:sslv3 alert handshake failure When I use curl, it fails by default but succeeds with the -3 option. curl https://username:Password@helloworldurl -3 This leads me to believe that it is the SSL version, which I found may be badly supported on ubuntu while searching the error. Sooo. How do I change or check the SSL version using python preferably with requests. Note: the url is private and cannot be given out. Sorry.

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  • SQL03070: This statement is not recognized in this context

    - by prash
    Recently I have started working with VS2010 and Fx4. There have been various challenges. We also introduced a new Database Project in our solution. And found this error. The reason for this error is: the project system expects the stored procedure as a create statement only.  The additional statements to drop if existing are not necessary within the project system.  Project deployment takes care of detecting if the sproc already exists and if it needs to be updated. To resolve this error you can simply remove the additional statements other then your create SP, Function etc. OR Exclude the file from build. Right Click on your file in Solution Explorer, Click Properties > Build Action > Not in Build

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  • nvcc not found, but only when using sudo

    - by dsp_099
    I can't get ANYTHING working on linux. I'm trying to compile CudaMiner. sudo make: ypt-jane.o `test -f 'scrypt-jane.cpp' || echo './'`scrypt-jane.cpp mv -f .deps/cudaminer-scrypt-jane.Tpo .deps/cudaminer-scrypt-jane.Po nvcc -g -O2 -Xptxas "-abi=no -v" -arch=compute_10 --maxrregcount=64 --ptxas-options=-v -I./compat/jansson -o salsa_kernel.o -c salsa_kernel.cu /bin/bash: nvcc: command not found make[2]: *** [salsa_kernel.o] Error 127 make[2]: Leaving directory `/var/progs/CudaMiner' make[1]: *** [all-recursive] Error 1 make[1]: Leaving directory `/var/progs/CudaMiner' make: *** [all] Error 2 So, kind of interesting: nvcc: nvcc fatal : No input files specified; use option --help for more information Whereas sudo nvcc: sudo: nvcc: command not found Huh?? I have identical exports listed in ~/.bashrc AND /etc/bash.bashrc. (Nvcc is located in: /usr/local/cuda-5.0/bin/nvcc) I also tried changing the current path, to no avail: $ sudo bash -c 'echo $PATH' /usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin $ PATH=$PATH:/usr/local/cuda-5.0/bin/nvcc $ sudo bash -c 'echo $PATH' /usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin Thanks in advance!

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  • Cannot Install/Start MySQL Server

    - by Peezy Bro
    Okay, I decided to migrate from MySQL Server 5.5.37 to Percona Server 5.6. I ended up removing MySQL Server by the following: sudo apt-get --purge remove mysql-server mysql-server-5.5 mysql-server-core-5.5 mysql-client mysql-client-core-5.5 mysql-common sudo apt-get autoremove sudo apt-get autoclean rm -rf /var/lib/mysql rm -rf /etc/mysql Now here is my problem, when I try to install MySQL Server 5.6 it goes through its process and when it asks me for a password, it comes up with Cannot set MySQL "root" password. After it "installs" MySQL wont start up and I get permission denied?. Reading package lists... Done Building dependency tree Reading state information... Done 0 upgraded, 0 newly installed, 0 to remove and 35 not upgraded. brandon@brandon-DB:~$ sudo apt-get install mysql-server Reading package lists... Done Building dependency tree Reading state information... Done The following extra packages will be installed: libdbd-mysql-perl libdbi-perl libmysqlclient18 libterm-readkey-perl mysql-client-5.5 mysql-client-core-5.5 mysql-common mysql-server-5.5 mysql-server-core-5.5 Suggested packages: libmldbm-perl libnet-daemon-perl libplrpc-perl libsql-statement-perl tinyca mailx The following NEW packages will be installed: libdbd-mysql-perl libdbi-perl libmysqlclient18 libterm-readkey-perl mysql-client-5.5 mysql-client-core-5.5 mysql-common mysql-server mysql-server-5.5 mysql-server-core-5.5 0 upgraded, 10 newly installed, 0 to remove and 35 not upgraded. Need to get 0 B/8,955 kB of archives. After this operation, 96.3 MB of additional disk space will be used. Do you want to continue? [Y/n] y Preconfiguring packages ... Selecting previously unselected package mysql-common. (Reading database ... 167760 files and directories currently installed.) Preparing to unpack .../mysql-common_5.5.37-0ubuntu0.14.04.1_all.deb ... Unpacking mysql-common (5.5.37-0ubuntu0.14.04.1) ... Selecting previously unselected package libmysqlclient18:amd64. Preparing to unpack .../libmysqlclient18_5.5.37-0ubuntu0.14.04.1_amd64.deb ... Unpacking libmysqlclient18:amd64 (5.5.37-0ubuntu0.14.04.1) ... Selecting previously unselected package libdbi-perl. Preparing to unpack .../libdbi-perl_1.630-1_amd64.deb ... Unpacking libdbi-perl (1.630-1) ... Selecting previously unselected package libdbd-mysql-perl. Preparing to unpack .../libdbd-mysql-perl_4.025-1_amd64.deb ... Unpacking libdbd-mysql-perl (4.025-1) ... Selecting previously unselected package libterm-readkey-perl. Preparing to unpack .../libterm-readkey-perl_2.31-1_amd64.deb ... Unpacking libterm-readkey-perl (2.31-1) ... Selecting previously unselected package mysql-client-core-5.5. Preparing to unpack .../mysql-client-core-5.5_5.5.37-0ubuntu0.14.04.1_amd64.deb ... Unpacking mysql-client-core-5.5 (5.5.37-0ubuntu0.14.04.1) ... Selecting previously unselected package mysql-client-5.5. Preparing to unpack .../mysql-client-5.5_5.5.37-0ubuntu0.14.04.1_amd64.deb ... Unpacking mysql-client-5.5 (5.5.37-0ubuntu0.14.04.1) ... Selecting previously unselected package mysql-server-core-5.5. Preparing to unpack .../mysql-server-core-5.5_5.5.37-0ubuntu0.14.04.1_amd64.deb ... Unpacking mysql-server-core-5.5 (5.5.37-0ubuntu0.14.04.1) ... Processing triggers for man-db (2.6.7.1-1) ... Setting up mysql-common (5.5.37-0ubuntu0.14.04.1) ... Selecting previously unselected package mysql-server-5.5. (Reading database ... 168116 files and directories currently installed.) Preparing to unpack .../mysql-server-5.5_5.5.37-0ubuntu0.14.04.1_amd64.deb ... Unpacking mysql-server-5.5 (5.5.37-0ubuntu0.14.04.1) ... Selecting previously unselected package mysql-server. Preparing to unpack .../mysql-server_5.5.37-0ubuntu0.14.04.1_all.deb ... Unpacking mysql-server (5.5.37-0ubuntu0.14.04.1) ... Processing triggers for ureadahead (0.100.0-16) ... Processing triggers for man-db (2.6.7.1-1) ... Setting up libmysqlclient18:amd64 (5.5.37-0ubuntu0.14.04.1) ... Setting up libdbi-perl (1.630-1) ... Setting up libdbd-mysql-perl (4.025-1) ... Setting up libterm-readkey-perl (2.31-1) ... Setting up mysql-client-core-5.5 (5.5.37-0ubuntu0.14.04.1) ... Setting up mysql-client-5.5 (5.5.37-0ubuntu0.14.04.1) ... Setting up mysql-server-core-5.5 (5.5.37-0ubuntu0.14.04.1) ... Setting up mysql-server-5.5 (5.5.37-0ubuntu0.14.04.1) ... start: Job failed to start invoke-rc.d: initscript mysql, action "start" failed. dpkg: error processing package mysql-server-5.5 (--configure): subprocess installed post-installation script returned error exit status 1 dpkg: dependency problems prevent configuration of mysql-server: mysql-server depends on mysql-server-5.5; however: Package mysql-server-5.5 is not configured yet. dpkg: error processing package mysql-server (--configure): dependency problems - leaving unconfigured Processing triggers for libc-bin (2.19-0ubuntu6) ... No apport report written because the error message indicates its a followup error from a previous failure. Processing triggers for ureadahead (0.100.0-16) ... Errors were encountered while processing: mysql-server-5.5 mysql-server E: Sub-process /usr/bin/dpkg returned an error code (1) I have all my database/tables dumped and on a seperate HDD. This is also a Dev Machine and not my main Production Machine. I also backed up the MySQL_Config and MySQL_Data.

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  • Google Chrome proxy settings?

    - by becko
    When I try to set Google Chrome's proxy settings (on chrome://linux-proxy-config/), I get the following message: When running Google Chrome under a supported desktop environment, the system proxy settings will be used. However, either your system is not supported or there was a problem launching your system configuration. But you can still configure via the command line. Please see man google-chrome-stable for more information on flags and environment variables. I need to set proxy settings to use Chrome, but I don't want to be setting them in the command line every time I use Chrome. Is there a way to set these settings permanently? Also, is there an option in Chrome so that it doesn't use proxy for specific domains (analogous to the No proxy for setting in Firefox)?

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  • Entity Framework Code-First, OData & Windows Phone Client

    - by Jon Galloway
    Entity Framework Code-First is the coolest thing since sliced bread, Windows  Phone is the hottest thing since Tickle-Me-Elmo and OData is just too great to ignore. As part of the Full Stack project, we wanted to put them together, which turns out to be pretty easy… once you know how.   EF Code-First CTP5 is available now and there should be very few breaking changes in the release edition, which is due early in 2011.  Note: EF Code-First evolved rapidly and many of the existing documents and blog posts which were written with earlier versions, may now be obsolete or at least misleading.   Code-First? With traditional Entity Framework you start with a database and from that you generate “entities” – classes that bridge between the relational database and your object oriented program. With Code-First (Magic-Unicorn) (see Hanselman’s write up and this later write up by Scott Guthrie) the Entity Framework looks at classes you created and says “if I had created these classes, the database would have to have looked like this…” and creates the database for you! By deriving your entity collections from DbSet and exposing them via a class that derives from DbContext, you "turn on" database backing for your POCO with a minimum of code and no hidden designer or configuration files. POCO == Plain Old CLR Objects Your entity objects can be used throughout your applications - in web applications, console applications, Silverlight and Windows Phone applications, etc. In our case, we'll want to read and update data from a Windows Phone client application, so we'll expose the entities through a DataService and hook the Windows Phone client application to that data via proxies.  Piece of Pie.  Easy as cake. The Demo Architecture To see this at work, we’ll create an ASP.NET/MVC application which will act as the host for our Data Service.  We’ll create an incredibly simple data layer using EF Code-First on top of SQLCE4 and we’ll expose the data in a WCF Data Service using the oData protocol.  Our Windows Phone 7 client will instantiate  the data context via a URI and load the data asynchronously. Setting up the Server project with MVC 3, EF Code First, and SQL CE 4 Create a new application of type ASP.NET MVC 3 and name it DeadSimpleServer.  We need to add the latest SQLCE4 and Entity Framework Code First CTP's to our project. Fortunately, NuGet makes that really easy. Open the Package Manager Console (View / Other Windows / Package Manager Console) and type in "Install-Package EFCodeFirst.SqlServerCompact" at the PM> command prompt. Since NuGet handles dependencies for you, you'll see that it installs everything you need to use Entity Framework Code First in your project. PM> install-package EFCodeFirst.SqlServerCompact 'SQLCE (= 4.0.8435.1)' not installed. Attempting to retrieve dependency from source... Done 'EFCodeFirst (= 0.8)' not installed. Attempting to retrieve dependency from source... Done 'WebActivator (= 1.0.0.0)' not installed. Attempting to retrieve dependency from source... Done You are downloading SQLCE from Microsoft, the license agreement to which is available at http://173.203.67.148/licenses/SQLCE/EULA_ENU.rtf. Check the package for additional dependencies, which may come with their own license agreement(s). Your use of the package and dependencies constitutes your acceptance of their license agreements. If you do not accept the license agreement(s), then delete the relevant components from your device. Successfully installed 'SQLCE 4.0.8435.1' You are downloading EFCodeFirst from Microsoft, the license agreement to which is available at http://go.microsoft.com/fwlink/?LinkID=206497. Check the package for additional dependencies, which may come with their own license agreement(s). Your use of the package and dependencies constitutes your acceptance of their license agreements. If you do not accept the license agreement(s), then delete the relevant components from your device. Successfully installed 'EFCodeFirst 0.8' Successfully installed 'WebActivator 1.0.0.0' You are downloading EFCodeFirst.SqlServerCompact from Microsoft, the license agreement to which is available at http://173.203.67.148/licenses/SQLCE/EULA_ENU.rtf. Check the package for additional dependencies, which may come with their own license agreement(s). Your use of the package and dependencies constitutes your acceptance of their license agreements. If you do not accept the license agreement(s), then delete the relevant components from your device. Successfully installed 'EFCodeFirst.SqlServerCompact 0.8' Successfully added 'SQLCE 4.0.8435.1' to EfCodeFirst-CTP5 Successfully added 'EFCodeFirst 0.8' to EfCodeFirst-CTP5 Successfully added 'WebActivator 1.0.0.0' to EfCodeFirst-CTP5 Successfully added 'EFCodeFirst.SqlServerCompact 0.8' to EfCodeFirst-CTP5 Note: We're using SQLCE 4 with Entity Framework here because they work really well together from a development scenario, but you can of course use Entity Framework Code First with other databases supported by Entity framework. Creating The Model using EF Code First Now we can create our model class. Right-click the Models folder and select Add/Class. Name the Class Person.cs and add the following code: using System.Data.Entity; namespace DeadSimpleServer.Models { public class Person { public int ID { get; set; } public string Name { get; set; } } public class PersonContext : DbContext { public DbSet<Person> People { get; set; } } } Notice that the entity class Person has no special interfaces or base class. There's nothing special needed to make it work - it's just a POCO. The context we'll use to access the entities in the application is called PersonContext, but you could name it anything you wanted. The important thing is that it inherits DbContext and contains one or more DbSet which holds our entity collections. Adding Seed Data We need some testing data to expose from our service. The simplest way to get that into our database is to modify the CreateCeDatabaseIfNotExists class in AppStart_SQLCEEntityFramework.cs by adding some seed data to the Seed method: protected virtual void Seed( TContext context ) { var personContext = context as PersonContext; personContext.People.Add( new Person { ID = 1, Name = "George Washington" } ); personContext.People.Add( new Person { ID = 2, Name = "John Adams" } ); personContext.People.Add( new Person { ID = 3, Name = "Thomas Jefferson" } ); personContext.SaveChanges(); } The CreateCeDatabaseIfNotExists class name is pretty self-explanatory - when our DbContext is accessed and the database isn't found, a new one will be created and populated with the data in the Seed method. There's one more step to make that work - we need to uncomment a line in the Start method at the top of of the AppStart_SQLCEEntityFramework class and set the context name, as shown here, public static class AppStart_SQLCEEntityFramework { public static void Start() { DbDatabase.DefaultConnectionFactory = new SqlCeConnectionFactory("System.Data.SqlServerCe.4.0"); // Sets the default database initialization code for working with Sql Server Compact databases // Uncomment this line and replace CONTEXT_NAME with the name of your DbContext if you are // using your DbContext to create and manage your database DbDatabase.SetInitializer(new CreateCeDatabaseIfNotExists<PersonContext>()); } } Now our database and entity framework are set up, so we can expose data via WCF Data Services. Note: This is a bare-bones implementation with no administration screens. If you'd like to see how those are added, check out The Full Stack screencast series. Creating the oData Service using WCF Data Services Add a new WCF Data Service to the project (right-click the project / Add New Item / Web / WCF Data Service). We’ll be exposing all the data as read/write.  Remember to reconfigure to control and minimize access as appropriate for your own application. Open the code behind for your service. In our case, the service was called PersonTestDataService.svc so the code behind class file is PersonTestDataService.svc.cs. using System.Data.Services; using System.Data.Services.Common; using System.ServiceModel; using DeadSimpleServer.Models; namespace DeadSimpleServer { [ServiceBehavior( IncludeExceptionDetailInFaults = true )] public class PersonTestDataService : DataService<PersonContext> { // This method is called only once to initialize service-wide policies. public static void InitializeService( DataServiceConfiguration config ) { config.SetEntitySetAccessRule( "*", EntitySetRights.All ); config.DataServiceBehavior.MaxProtocolVersion = DataServiceProtocolVersion.V2; config.UseVerboseErrors = true; } } } We're enabling a few additional settings to make it easier to debug if you run into trouble. The ServiceBehavior attribute is set to include exception details in faults, and we're using verbose errors. You can remove both of these when your service is working, as your public production service shouldn't be revealing exception information. You can view the output of the service by running the application and browsing to http://localhost:[portnumber]/PersonTestDataService.svc/: <service xml:base="http://localhost:49786/PersonTestDataService.svc/" xmlns:atom="http://www.w3.org/2005/Atom" xmlns:app="http://www.w3.org/2007/app" xmlns="http://www.w3.org/2007/app"> <workspace> <atom:title>Default</atom:title> <collection href="People"> <atom:title>People</atom:title> </collection> </workspace> </service> This indicates that the service exposes one collection, which is accessible by browsing to http://localhost:[portnumber]/PersonTestDataService.svc/People <?xml version="1.0" encoding="iso-8859-1" standalone="yes"?> <feed xml:base=http://localhost:49786/PersonTestDataService.svc/ xmlns:d="http://schemas.microsoft.com/ado/2007/08/dataservices" xmlns:m="http://schemas.microsoft.com/ado/2007/08/dataservices/metadata" xmlns="http://www.w3.org/2005/Atom"> <title type="text">People</title> <id>http://localhost:49786/PersonTestDataService.svc/People</id> <updated>2010-12-29T01:01:50Z</updated> <link rel="self" title="People" href="People" /> <entry> <id>http://localhost:49786/PersonTestDataService.svc/People(1)</id> <title type="text"></title> <updated>2010-12-29T01:01:50Z</updated> <author> <name /> </author> <link rel="edit" title="Person" href="People(1)" /> <category term="DeadSimpleServer.Models.Person" scheme="http://schemas.microsoft.com/ado/2007/08/dataservices/scheme" /> <content type="application/xml"> <m:properties> <d:ID m:type="Edm.Int32">1</d:ID> <d:Name>George Washington</d:Name> </m:properties> </content> </entry> <entry> ... </entry> </feed> Let's recap what we've done so far. But enough with services and XML - let's get this into our Windows Phone client application. Creating the DataServiceContext for the Client Use the latest DataSvcUtil.exe from http://odata.codeplex.com. As of today, that's in this download: http://odata.codeplex.com/releases/view/54698 You need to run it with a few options: /uri - This will point to the service URI. In this case, it's http://localhost:59342/PersonTestDataService.svc  Pick up the port number from your running server (e.g., the server formerly known as Cassini). /out - This is the DataServiceContext class that will be generated. You can name it whatever you'd like. /Version - should be set to 2.0 /DataServiceCollection - Include this flag to generate collections derived from the DataServiceCollection base, which brings in all the ObservableCollection goodness that handles your INotifyPropertyChanged events for you. Here's the console session from when we ran it: <ListBox x:Name="MainListBox" Margin="0,0,-12,0" ItemsSource="{Binding}" SelectionChanged="MainListBox_SelectionChanged"> Next, to keep things simple, change the Binding on the two TextBlocks within the DataTemplate to Name and ID, <ListBox x:Name="MainListBox" Margin="0,0,-12,0" ItemsSource="{Binding}" SelectionChanged="MainListBox_SelectionChanged"> <ListBox.ItemTemplate> <DataTemplate> <StackPanel Margin="0,0,0,17" Width="432"> <TextBlock Text="{Binding Name}" TextWrapping="Wrap" Style="{StaticResource PhoneTextExtraLargeStyle}" /> <TextBlock Text="{Binding ID}" TextWrapping="Wrap" Margin="12,-6,12,0" Style="{StaticResource PhoneTextSubtleStyle}" /> </StackPanel> </DataTemplate> </ListBox.ItemTemplate> </ListBox> Getting The Context In the code-behind you’ll first declare a member variable to hold the context from the Entity Framework. This is named using convention over configuration. The db type is Person and the context is of type PersonContext, You initialize it by providing the URI, in this case using the URL obtained from the Cassini web server, PersonContext context = new PersonContext( new Uri( "http://localhost:49786/PersonTestDataService.svc/" ) ); Create a second member variable of type DataServiceCollection<Person> but do not initialize it, DataServiceCollection<Person> people; In the constructor you’ll initialize the DataServiceCollection using the PersonContext, public MainPage() { InitializeComponent(); people = new DataServiceCollection<Person>( context ); Finally, you’ll load the people collection using the LoadAsync method, passing in the fully specified URI for the People collection in the web service, people.LoadAsync( new Uri( "http://localhost:49786/PersonTestDataService.svc/People" ) ); Note that this method runs asynchronously and when it is finished the people  collection is already populated. Thus, since we didn’t need or want to override any of the behavior we don’t implement the LoadCompleted. You can use the LoadCompleted event if you need to do any other UI updates, but you don't need to. The final code is as shown below: using System; using System.Data.Services.Client; using System.Windows; using System.Windows.Controls; using DeadSimpleServer.Models; using Microsoft.Phone.Controls; namespace WindowsPhoneODataTest { public partial class MainPage : PhoneApplicationPage { PersonContext context = new PersonContext( new Uri( "http://localhost:49786/PersonTestDataService.svc/" ) ); DataServiceCollection<Person> people; // Constructor public MainPage() { InitializeComponent(); // Set the data context of the listbox control to the sample data // DataContext = App.ViewModel; people = new DataServiceCollection<Person>( context ); people.LoadAsync( new Uri( "http://localhost:49786/PersonTestDataService.svc/People" ) ); DataContext = people; this.Loaded += new RoutedEventHandler( MainPage_Loaded ); } // Handle selection changed on ListBox private void MainListBox_SelectionChanged( object sender, SelectionChangedEventArgs e ) { // If selected index is -1 (no selection) do nothing if ( MainListBox.SelectedIndex == -1 ) return; // Navigate to the new page NavigationService.Navigate( new Uri( "/DetailsPage.xaml?selectedItem=" + MainListBox.SelectedIndex, UriKind.Relative ) ); // Reset selected index to -1 (no selection) MainListBox.SelectedIndex = -1; } // Load data for the ViewModel Items private void MainPage_Loaded( object sender, RoutedEventArgs e ) { if ( !App.ViewModel.IsDataLoaded ) { App.ViewModel.LoadData(); } } } } With people populated we can set it as the DataContext and run the application; you’ll find that the Name and ID are displayed in the list on the Mainpage. Here's how the pieces in the client fit together: Complete source code available here

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  • C#/.NET Little Wonders: The Concurrent Collections (1 of 3)

    - by James Michael Hare
    Once again we consider some of the lesser known classes and keywords of C#.  In the next few weeks, we will discuss the concurrent collections and how they have changed the face of concurrent programming. This week’s post will begin with a general introduction and discuss the ConcurrentStack<T> and ConcurrentQueue<T>.  Then in the following post we’ll discuss the ConcurrentDictionary<T> and ConcurrentBag<T>.  Finally, we shall close on the third post with a discussion of the BlockingCollection<T>. For more of the "Little Wonders" posts, see the index here. A brief history of collections In the beginning was the .NET 1.0 Framework.  And out of this framework emerged the System.Collections namespace, and it was good.  It contained all the basic things a growing programming language needs like the ArrayList and Hashtable collections.  The main problem, of course, with these original collections is that they held items of type object which means you had to be disciplined enough to use them correctly or you could end up with runtime errors if you got an object of a type you weren't expecting. Then came .NET 2.0 and generics and our world changed forever!  With generics the C# language finally got an equivalent of the very powerful C++ templates.  As such, the System.Collections.Generic was born and we got type-safe versions of all are favorite collections.  The List<T> succeeded the ArrayList and the Dictionary<TKey,TValue> succeeded the Hashtable and so on.  The new versions of the library were not only safer because they checked types at compile-time, in many cases they were more performant as well.  So much so that it's Microsoft's recommendation that the System.Collections original collections only be used for backwards compatibility. So we as developers came to know and love the generic collections and took them into our hearts and embraced them.  The problem is, thread safety in both the original collections and the generic collections can be problematic, for very different reasons. Now, if you are only doing single-threaded development you may not care – after all, no locking is required.  Even if you do have multiple threads, if a collection is “load-once, read-many” you don’t need to do anything to protect that container from multi-threaded access, as illustrated below: 1: public static class OrderTypeTranslator 2: { 3: // because this dictionary is loaded once before it is ever accessed, we don't need to synchronize 4: // multi-threaded read access 5: private static readonly Dictionary<string, char> _translator = new Dictionary<string, char> 6: { 7: {"New", 'N'}, 8: {"Update", 'U'}, 9: {"Cancel", 'X'} 10: }; 11:  12: // the only public interface into the dictionary is for reading, so inherently thread-safe 13: public static char? Translate(string orderType) 14: { 15: char charValue; 16: if (_translator.TryGetValue(orderType, out charValue)) 17: { 18: return charValue; 19: } 20:  21: return null; 22: } 23: } Unfortunately, most of our computer science problems cannot get by with just single-threaded applications or with multi-threading in a load-once manner.  Looking at  today's trends, it's clear to see that computers are not so much getting faster because of faster processor speeds -- we've nearly reached the limits we can push through with today's technologies -- but more because we're adding more cores to the boxes.  With this new hardware paradigm, it is even more important to use multi-threaded applications to take full advantage of parallel processing to achieve higher application speeds. So let's look at how to use collections in a thread-safe manner. Using historical collections in a concurrent fashion The early .NET collections (System.Collections) had a Synchronized() static method that could be used to wrap the early collections to make them completely thread-safe.  This paradigm was dropped in the generic collections (System.Collections.Generic) because having a synchronized wrapper resulted in atomic locks for all operations, which could prove overkill in many multithreading situations.  Thus the paradigm shifted to having the user of the collection specify their own locking, usually with an external object: 1: public class OrderAggregator 2: { 3: private static readonly Dictionary<string, List<Order>> _orders = new Dictionary<string, List<Order>>(); 4: private static readonly _orderLock = new object(); 5:  6: public void Add(string accountNumber, Order newOrder) 7: { 8: List<Order> ordersForAccount; 9:  10: // a complex operation like this should all be protected 11: lock (_orderLock) 12: { 13: if (!_orders.TryGetValue(accountNumber, out ordersForAccount)) 14: { 15: _orders.Add(accountNumber, ordersForAccount = new List<Order>()); 16: } 17:  18: ordersForAccount.Add(newOrder); 19: } 20: } 21: } Notice how we’re performing several operations on the dictionary under one lock.  With the Synchronized() static methods of the early collections, you wouldn’t be able to specify this level of locking (a more macro-level).  So in the generic collections, it was decided that if a user needed synchronization, they could implement their own locking scheme instead so that they could provide synchronization as needed. The need for better concurrent access to collections Here’s the problem: it’s relatively easy to write a collection that locks itself down completely for access, but anything more complex than that can be difficult and error-prone to write, and much less to make it perform efficiently!  For example, what if you have a Dictionary that has frequent reads but in-frequent updates?  Do you want to lock down the entire Dictionary for every access?  This would be overkill and would prevent concurrent reads.  In such cases you could use something like a ReaderWriterLockSlim which allows for multiple readers in a lock, and then once a writer grabs the lock it blocks all further readers until the writer is done (in a nutshell).  This is all very complex stuff to consider. Fortunately, this is where the Concurrent Collections come in.  The Parallel Computing Platform team at Microsoft went through great pains to determine how to make a set of concurrent collections that would have the best performance characteristics for general case multi-threaded use. Now, as in all things involving threading, you should always make sure you evaluate all your container options based on the particular usage scenario and the degree of parallelism you wish to acheive. This article should not be taken to understand that these collections are always supperior to the generic collections. Each fills a particular need for a particular situation. Understanding what each container is optimized for is key to the success of your application whether it be single-threaded or multi-threaded. General points to consider with the concurrent collections The MSDN points out that the concurrent collections all support the ICollection interface. However, since the collections are already synchronized, the IsSynchronized property always returns false, and SyncRoot always returns null.  Thus you should not attempt to use these properties for synchronization purposes. Note that since the concurrent collections also may have different operations than the traditional data structures you may be used to.  Now you may ask why they did this, but it was done out of necessity to keep operations safe and atomic.  For example, in order to do a Pop() on a stack you have to know the stack is non-empty, but between the time you check the stack’s IsEmpty property and then do the Pop() another thread may have come in and made the stack empty!  This is why some of the traditional operations have been changed to make them safe for concurrent use. In addition, some properties and methods in the concurrent collections achieve concurrency by creating a snapshot of the collection, which means that some operations that were traditionally O(1) may now be O(n) in the concurrent models.  I’ll try to point these out as we talk about each collection so you can be aware of any potential performance impacts.  Finally, all the concurrent containers are safe for enumeration even while being modified, but some of the containers support this in different ways (snapshot vs. dirty iteration).  Once again I’ll highlight how thread-safe enumeration works for each collection. ConcurrentStack<T>: The thread-safe LIFO container The ConcurrentStack<T> is the thread-safe counterpart to the System.Collections.Generic.Stack<T>, which as you may remember is your standard last-in-first-out container.  If you think of algorithms that favor stack usage (for example, depth-first searches of graphs and trees) then you can see how using a thread-safe stack would be of benefit. The ConcurrentStack<T> achieves thread-safe access by using System.Threading.Interlocked operations.  This means that the multi-threaded access to the stack requires no traditional locking and is very, very fast! For the most part, the ConcurrentStack<T> behaves like it’s Stack<T> counterpart with a few differences: Pop() was removed in favor of TryPop() Returns true if an item existed and was popped and false if empty. PushRange() and TryPopRange() were added Allows you to push multiple items and pop multiple items atomically. Count takes a snapshot of the stack and then counts the items. This means it is a O(n) operation, if you just want to check for an empty stack, call IsEmpty instead which is O(1). ToArray() and GetEnumerator() both also take snapshots. This means that iteration over a stack will give you a static view at the time of the call and will not reflect updates. Pushing on a ConcurrentStack<T> works just like you’d expect except for the aforementioned PushRange() method that was added to allow you to push a range of items concurrently. 1: var stack = new ConcurrentStack<string>(); 2:  3: // adding to stack is much the same as before 4: stack.Push("First"); 5:  6: // but you can also push multiple items in one atomic operation (no interleaves) 7: stack.PushRange(new [] { "Second", "Third", "Fourth" }); For looking at the top item of the stack (without removing it) the Peek() method has been removed in favor of a TryPeek().  This is because in order to do a peek the stack must be non-empty, but between the time you check for empty and the time you execute the peek the stack contents may have changed.  Thus the TryPeek() was created to be an atomic check for empty, and then peek if not empty: 1: // to look at top item of stack without removing it, can use TryPeek. 2: // Note that there is no Peek(), this is because you need to check for empty first. TryPeek does. 3: string item; 4: if (stack.TryPeek(out item)) 5: { 6: Console.WriteLine("Top item was " + item); 7: } 8: else 9: { 10: Console.WriteLine("Stack was empty."); 11: } Finally, to remove items from the stack, we have the TryPop() for single, and TryPopRange() for multiple items.  Just like the TryPeek(), these operations replace Pop() since we need to ensure atomically that the stack is non-empty before we pop from it: 1: // to remove items, use TryPop or TryPopRange to get multiple items atomically (no interleaves) 2: if (stack.TryPop(out item)) 3: { 4: Console.WriteLine("Popped " + item); 5: } 6:  7: // TryPopRange will only pop up to the number of spaces in the array, the actual number popped is returned. 8: var poppedItems = new string[2]; 9: int numPopped = stack.TryPopRange(poppedItems); 10:  11: foreach (var theItem in poppedItems.Take(numPopped)) 12: { 13: Console.WriteLine("Popped " + theItem); 14: } Finally, note that as stated before, GetEnumerator() and ToArray() gets a snapshot of the data at the time of the call.  That means if you are enumerating the stack you will get a snapshot of the stack at the time of the call.  This is illustrated below: 1: var stack = new ConcurrentStack<string>(); 2:  3: // adding to stack is much the same as before 4: stack.Push("First"); 5:  6: var results = stack.GetEnumerator(); 7:  8: // but you can also push multiple items in one atomic operation (no interleaves) 9: stack.PushRange(new [] { "Second", "Third", "Fourth" }); 10:  11: while(results.MoveNext()) 12: { 13: Console.WriteLine("Stack only has: " + results.Current); 14: } The only item that will be printed out in the above code is "First" because the snapshot was taken before the other items were added. This may sound like an issue, but it’s really for safety and is more correct.  You don’t want to enumerate a stack and have half a view of the stack before an update and half a view of the stack after an update, after all.  In addition, note that this is still thread-safe, whereas iterating through a non-concurrent collection while updating it in the old collections would cause an exception. ConcurrentQueue<T>: The thread-safe FIFO container The ConcurrentQueue<T> is the thread-safe counterpart of the System.Collections.Generic.Queue<T> class.  The concurrent queue uses an underlying list of small arrays and lock-free System.Threading.Interlocked operations on the head and tail arrays.  Once again, this allows us to do thread-safe operations without the need for heavy locks! The ConcurrentQueue<T> (like the ConcurrentStack<T>) has some departures from the non-concurrent counterpart.  Most notably: Dequeue() was removed in favor of TryDequeue(). Returns true if an item existed and was dequeued and false if empty. Count does not take a snapshot It subtracts the head and tail index to get the count.  This results overall in a O(1) complexity which is quite good.  It’s still recommended, however, that for empty checks you call IsEmpty instead of comparing Count to zero. ToArray() and GetEnumerator() both take snapshots. This means that iteration over a queue will give you a static view at the time of the call and will not reflect updates. The Enqueue() method on the ConcurrentQueue<T> works much the same as the generic Queue<T>: 1: var queue = new ConcurrentQueue<string>(); 2:  3: // adding to queue is much the same as before 4: queue.Enqueue("First"); 5: queue.Enqueue("Second"); 6: queue.Enqueue("Third"); For front item access, the TryPeek() method must be used to attempt to see the first item if the queue.  There is no Peek() method since, as you’ll remember, we can only peek on a non-empty queue, so we must have an atomic TryPeek() that checks for empty and then returns the first item if the queue is non-empty. 1: // to look at first item in queue without removing it, can use TryPeek. 2: // Note that there is no Peek(), this is because you need to check for empty first. TryPeek does. 3: string item; 4: if (queue.TryPeek(out item)) 5: { 6: Console.WriteLine("First item was " + item); 7: } 8: else 9: { 10: Console.WriteLine("Queue was empty."); 11: } Then, to remove items you use TryDequeue().  Once again this is for the same reason we have TryPeek() and not Peek(): 1: // to remove items, use TryDequeue. If queue is empty returns false. 2: if (queue.TryDequeue(out item)) 3: { 4: Console.WriteLine("Dequeued first item " + item); 5: } Just like the concurrent stack, the ConcurrentQueue<T> takes a snapshot when you call ToArray() or GetEnumerator() which means that subsequent updates to the queue will not be seen when you iterate over the results.  Thus once again the code below will only show the first item, since the other items were added after the snapshot. 1: var queue = new ConcurrentQueue<string>(); 2:  3: // adding to queue is much the same as before 4: queue.Enqueue("First"); 5:  6: var iterator = queue.GetEnumerator(); 7:  8: queue.Enqueue("Second"); 9: queue.Enqueue("Third"); 10:  11: // only shows First 12: while (iterator.MoveNext()) 13: { 14: Console.WriteLine("Dequeued item " + iterator.Current); 15: } Using collections concurrently You’ll notice in the examples above I stuck to using single-threaded examples so as to make them deterministic and the results obvious.  Of course, if we used these collections in a truly multi-threaded way the results would be less deterministic, but would still be thread-safe and with no locking on your part required! For example, say you have an order processor that takes an IEnumerable<Order> and handles each other in a multi-threaded fashion, then groups the responses together in a concurrent collection for aggregation.  This can be done easily with the TPL’s Parallel.ForEach(): 1: public static IEnumerable<OrderResult> ProcessOrders(IEnumerable<Order> orderList) 2: { 3: var proxy = new OrderProxy(); 4: var results = new ConcurrentQueue<OrderResult>(); 5:  6: // notice that we can process all these in parallel and put the results 7: // into our concurrent collection without needing any external locking! 8: Parallel.ForEach(orderList, 9: order => 10: { 11: var result = proxy.PlaceOrder(order); 12:  13: results.Enqueue(result); 14: }); 15:  16: return results; 17: } Summary Obviously, if you do not need multi-threaded safety, you don’t need to use these collections, but when you do need multi-threaded collections these are just the ticket! The plethora of features (I always think of the movie The Three Amigos when I say plethora) built into these containers and the amazing way they acheive thread-safe access in an efficient manner is wonderful to behold. Stay tuned next week where we’ll continue our discussion with the ConcurrentBag<T> and the ConcurrentDictionary<TKey,TValue>. For some excellent information on the performance of the concurrent collections and how they perform compared to a traditional brute-force locking strategy, see this wonderful whitepaper by the Microsoft Parallel Computing Platform team here.   Tweet Technorati Tags: C#,.NET,Concurrent Collections,Collections,Multi-Threading,Little Wonders,BlackRabbitCoder,James Michael Hare

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  • How can I upgrade to 10.10 from 10.10 beta

    - by n179911
    Can you please tell me how can I upgrade to ubuntu 10.10 release from ubuntu 10.10 beta? I have go to update manager, it keeps saying there is no update. And what I go to synaptic package manager, I see this error: W: A error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: http://extras.ubuntu.com maverick Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 16126D3A3E5C1192 W: Failed to fetch http://extras.ubuntu.com/ubuntu/dists/maverick/Release W: Some index files failed to download, they have been ignored, or old ones used instead.

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  • Google-bot sees “Sorry, we have no imagery here” on pages with Google Maps

    - by friism
    I have a site with Google Maps on most of the pages. When inspecting content keywords in Google Webmaster tools, content keywords identified by Google-bot for the site include "imagery", "sorry" and "here". These turn out to be part of an error message returned by Google Maps: "Sorry, we have no imagery here". I cannot reproduce this error with normal clients, nor does "fetch as Google" show it. The problem is presumably that Google-bot tries to execute some of the Google Maps Javascript but then shoots itself on the foot and records the error message. A Google search for "Sorry, we have no imagery here" shows that this problem is endemic to sites across the internet, including Yelp and many others. I'd like to convince Google that my site is not about imagery and being sorry, but I'd also like to keep the maps in place. I guess one option would be to transition to static maps, but that's not a great alternative. There's some related discussion on Webmaster World, no resolution.

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  • How to Troubleshoot TFS Build Server Failure?

    - by Tarun Arora
    Ever found your self in this helpless situation where you think you have tried every possible suggestion on the internet to bring the build server back but it just won’t work. Well some times before hunting around for a solution it is important to understand what the problem is, if the error messages in the build logs don’t seem to help you can always enable tracing on the build server to get more information on what could possibly be the root cause of failure. In this blog post today I’ll be showing you how to enable tracing on, - TFS 2010/11 Server - Build Server - Client Enable Tracing on Team Foundation Server 2010/2011 On the Team Foundation Server navigate to C:\Program Files\Microsoft Team Foundation Server 2010\Application Tier\Web Services, right click web.config and from the context menu select edit.          Search for the <appSettings> node in the config file and set the value of the key ‘traceWriter’ to true.          In the <System.diagnostics> tag set the value of switches from 0 to 4 to set the trace level to maximum to write diagnostics level trace information.          Restart the TFS Application pool to force this change to take effect. The application pool restart will impact any one using the TFS server at present. Note - It is recommended that you do not make any changes to the TFS production application server, this can have serious consequences and can even jeopardize the installation of your server.          Download the Debug view tool from http://technet.microsoft.com/en-us/sysinternals/bb896647.aspx and set it to capture “Global Events”. Perform any actions in the Team Explorer on the client machine, you should be able to see a series of trace data in the debug view tool now.         Enable Tracing on Build Controller/Agents Log on to the Build Controller/Agent and Navigate to the directory C:\Program Files\Microsoft Team Foundation Server 2010\Tools         Look for the configuration file ‘TFSBuildServiceHost.exe.config’ if it is not already there create a new text file and rename it to ‘TFSBuildServiceHost.exe.config’         To Enable tracing uncomment the <system.diagnostics> and paste the snippet below if it is not already there. <configuration> <system.diagnostics> <switches> <add name="BuildServiceTraceLevel" value="4"/> </switches> <trace autoflush="true" indentsize="4"> <listeners> <add name="myListener" type="Microsoft.TeamFoundation.TeamFoundationTextWriterTraceListener, Microsoft.TeamFoundation.Common, Version=10.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" initializeData="c:\logs\TFSBuildServiceHost.exe.log" /> <remove name="Default" /> </listeners> </trace> </system.diagnostics> </configuration> The highlighted path above is where the Log file will be created. If the folder is not already there then create the folder, also, make sure that the account running the build service has access to write to this folder.         Restart the build Controller/Agent service from the administration console (or net stop tfsbuildservicehost & net start tfsbuildservicehost) in order for the new setting to be picked up.         Enable TFS Tracing on the Client Machine On the client machine, shut down Visual Studio, navigate to C:\Program Files\Microsoft Visual Studio 10.0\Common 7\IDE          Search for devenv.exe.config, make a backup copy of the config file and right click the file and from the context menu select edit. If its not already there create this file.          Edit devenv.exe.config by adding the below code snippet before the last </configuration> tag <system.diagnostics> <switches> <add name="TeamFoundationSoapProxy" value="4" /> <add name="VersionControl" value="4" /> </switches> <trace autoflush="true" indentsize="3"> <listeners> <add name="myListener" type="Microsoft.TeamFoundation.TeamFoundationTextWriterTraceListener,Microsoft.TeamFoundation.Common, Version=10.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" initializeData="c:\tf.log" /> <add name="perfListener" type="Microsoft.TeamFoundation.Client.PerfTraceListener, Microsoft.TeamFoundation.Client, Version=10.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a"/> </listeners> </trace> </system.diagnostics> The highlighted path above is where the Log file will be created. If the folder is not already there then create the folder. Start Visual Studio and after a bit of activity you should be able to see the new log file being created on the folder specified in the config file. Other Resources Below are some Key resource you might like to review. I would highly recommend the documentation, walkthroughs and videos available on MSDN.   Thank you for taking the time out and reading this blog post. If you enjoyed the post, remember to subscribe to http://feeds.feedburner.com/TarunArora. Have you come across an interesting one to one with the build server, please share your experience here. Questions/Feedback/Suggestions, etc please leave a comment. Thank You! Share this post : CodeProject

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  • HTG Explains: What “Everything Is a File” Means on Linux

    - by Chris Hoffman
    One of the defining features of Linux and other UNIX-like operating systems is that “everything is a file.” This is an oversimplification, but understanding what it means will help you understand how Linux works. Many things on Linux appear in your file system, but they aren’t actually files. They’re special files that represent hardware devices, system information, and other things — including a random number generator. These special files may be located in pseudo or virtual file systems such as /dev, which contains special files that represent devices, and /proc, which contains special files that represent system and process information. How to Banish Duplicate Photos with VisiPic How to Make Your Laptop Choose a Wired Connection Instead of Wireless HTG Explains: What Is Two-Factor Authentication and Should I Be Using It?

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  • Cant correctly install Lazarus

    - by user206316
    I have a little problem with installing and running Lazarus. I just upgrade ubuntu from 13.04 to 13.10. When i had 13.04, i could install lazarus without any problems, but in 13.10 lazarus magicaly dissapeared, and when i tried install it from ubuntu software center, it said something like in my software resources lazarus-ide-0.9.30.4 doesnt exist. After some research on net i tried delete all files from earlier installations, download deb packages from sourceforge and install them, but when i want to instal fpc-src, error shows up with output: (Reading database ... 100% (Reading database ... 239063 files and directories currently installed.) Unpacking fpc-src (from .../Stiahnut/Lazarus/fpc-src.deb) ... dpkg: error processing /home/richi/Stiahnut/Lazarus/fpc-src.deb (--install): trying to overwrite '/usr/share/fpcsrc/2.6.2/rtl/nativent/tthread.inc', which is also in package fpc-source-2.6.2 2.6.2-5 dpkg-deb (subprocess): decompressing archive member: internal gzip write error: Broken pipe dpkg-deb: error: subprocess <decompress> returned error exit status 2 dpkg-deb (subprocess): cannot copy archive member from '/home/richi/Stiahnut/Lazarus/fpc-src.deb' to decompressor pipe: failed to write (Broken pipe) when i started lazarus, it of course tell me that it cant find fpc compier and fpc sources. So, please, i really need program for school and i dont wanna reinstall os anymore or something like that :( (Ubuntu 13.10 64bit) P.S: im not skilled in linux so if u know some commands to fix it just write them for copy and paste :) P.P.S:Sorry for bad English, im Slovak xD P.P.P.S: Thank so much for any answers update: output from sudo dpkg -l | grep "^rc" richi@Richi-Ubuntu:~/lazarus1.0.12$ sudo dpkg -l | grep "^rc" rc account-plugin-generic-oauth 0.10bzr13.03.26-0ubuntu1.1 amd64 GNOME Control Center account plugin for single signon - generic OAuth rc appmenu-gtk:amd64 12.10.3daily13.04.03-0ubuntu1 amd64 Export GTK menus over DBus rc appmenu-gtk3:amd64 12.10.3daily13.04.03-0ubuntu1 amd64 Export GTK menus over DBus rc fp-compiler-2.6.0 2.6.0-9 amd64 Free Pascal - compiler rc fp-utils-2.6.0 2.6.0-9 amd64 Free Pascal - utilities rc lazarus-ide-0.9.30.4 0.9.30.4-4 amd64 IDE for Free Pascal - common IDE files rc lazarus-ide-1.0.10 1.0.10+dfsg-1 amd64 IDE for Free Pascal - common IDE files rc lcl-utils-0.9.30.4 0.9.30.4-4 amd64 Lazarus Components Library - command line build tools rc lcl-utils-1.0.10 1.0.10+dfsg-1 amd64 Lazarus Components Library - command line build tools rc libbamf3-1:amd64 0.4.0daily13.06.19~13.04-0ubuntu1 amd64 Window matching library - shared library rc libboost-filesystem1.49.0 1.49.0-4 amd64 filesystem operations (portable paths, iteration over directories, etc) in C++ rc libboost-signals1.49.0 1.49.0-4 amd64 managed signals and slots library for C++ rc libboost-system1.49.0 1.49.0-4 amd64 Operating system (e.g. diagnostics support) library rc libboost-thread1.49.0 1.49.0-4 amd64 portable C++ multi-threading rc libbrlapi0.5:amd64 4.4-8ubuntu4 amd64 braille display access via BRLTTY - shared library rc libcamel-1.2-40 3.6.4-0ubuntu1.1 amd64 Evolution MIME message handling library rc libcolumbus0-0 0.4.0daily13.04.16~13.04-0ubuntu1 amd64 error tolerant matching engine - shared library rc libdns95 1:9.9.2.dfsg.P1-2ubuntu2.1 amd64 DNS Shared Library used by BIND rc libdvbpsi7 0.2.2-1 amd64 library for MPEG TS and DVB PSI tables decoding and generating rc libebackend-1.2-5 3.6.4-0ubuntu1.1 amd64 Utility library for evolution data servers rc libedata-book-1.2-15 3.6.4-0ubuntu1.1 amd64 Backend library for evolution address books rc libedata-cal-1.2-18 3.6.4-0ubuntu1.1 amd64 Backend library for evolution calendars rc libgc1c3:amd64 1:7.2d-0ubuntu5 amd64 conservative garbage collector for C and C++ rc libgd2-xpm:amd64 2.0.36~rc1~dfsg-6.1ubuntu1 amd64 GD Graphics Library version 2 rc libgd2-xpm:i386 2.0.36~rc1~dfsg-6.1ubuntu1 i386 GD Graphics Library version 2 rc libgnome-desktop-3-4 3.6.3-0ubuntu1 amd64 Utility library for loading .desktop files - runtime files rc libgphoto2-2:amd64 2.4.14-2 amd64 gphoto2 digital camera library rc libgphoto2-2:i386 2.4.14-2 i386 gphoto2 digital camera library rc libgphoto2-port0:amd64 2.4.14-2 amd64 gphoto2 digital camera port library rc libgphoto2-port0:i386 2.4.14-2 i386 gphoto2 digital camera port library rc libgtksourceview-3.0-0:amd64 3.6.3-0ubuntu1 amd64 shared libraries for the GTK+ syntax highlighting widget rc libgweather-3-1 3.6.2-0ubuntu1 amd64 GWeather shared library rc libharfbuzz0:amd64 0.9.13-1 amd64 OpenType text shaping engine rc libibus-1.0-0:amd64 1.4.2-0ubuntu2 amd64 Intelligent Input Bus - shared library rc libical0 0.48-2 amd64 iCalendar library implementation in C (runtime) rc libimobiledevice3 1.1.4-1ubuntu6.2 amd64 Library for communicating with the iPhone and iPod Touch rc libisc92 1:9.9.2.dfsg.P1-2ubuntu2.1 amd64 ISC Shared Library used by BIND rc libkms1:amd64 2.4.46-1 amd64 Userspace interface to kernel DRM buffer management rc libllvm3.2:i386 1:3.2repack-7ubuntu1 i386 Low-Level Virtual Machine (LLVM), runtime library rc libmikmod2:amd64 3.1.12-5 amd64 Portable sound library rc libpackagekit-glib2-14:amd64 0.7.6-3ubuntu1 amd64 Library for accessing PackageKit using GLib rc libpoppler28:amd64 0.20.5-1ubuntu3 amd64 PDF rendering library rc libraw5:amd64 0.14.7-0ubuntu1.13.04.2 amd64 raw image decoder library rc librhythmbox-core6 2.98-0ubuntu5 amd64 support library for the rhythmbox music player rc libsdl-mixer1.2:amd64 1.2.12-7ubuntu1 amd64 Mixer library for Simple DirectMedia Layer 1.2, libraries rc libsnmp15 5.4.3~dfsg-2.7ubuntu1 amd64 SNMP (Simple Network Management Protocol) library rc libsyncdaemon-1.0-1 4.2.0-0ubuntu1 amd64 Ubuntu One synchronization daemon library rc libunity-core-6.0-5 7.0.0daily13.06.19~13.04-0ubuntu1 amd64 Core library for the Unity interface. rc libusb-0.1-4:i386 2:0.1.12-23.2ubuntu1 i386 userspace USB programming library rc libwayland0:amd64 1.0.5-0ubuntu1 amd64 wayland compositor infrastructure - shared libraries rc linux-image-3.8.0-19-generic 3.8.0-19.30 amd64 Linux kernel image for version 3.8.0 on 64 bit x86 SMP rc linux-image-3.8.0-31-generic 3.8.0-31.46 amd64 Linux kernel image for version 3.8.0 on 64 bit x86 SMP rc linux-image-extra-3.8.0-19-generic 3.8.0-19.30 amd64 Linux kernel image for version 3.8.0 on 64 bit x86 SMP rc linux-image-extra-3.8.0-31-generic 3.8.0-31.46 amd64 Linux kernel image for version 3.8.0 on 64 bit x86 SMP rc screen-resolution-extra 0.15ubuntu1 all Extension for the GNOME screen resolution applet rc unity-common 7.0.0daily13.06.19~13.04-0ubuntu1 all Common files for the Unity interface.

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  • VSTO Troubleshooting Quick Tips

    - by João Angelo
    If you ever find yourself troubleshooting a VSTO addin that does not load then these steps will interest you. Do not skip the basics and check the registry at HKLM\Software\Microsoft\Office\<Application>\AddIns\<AddInName> or HKCU\Software\Microsoft\Office\<Product>\AddIns\<Application> because if the LoadBehavior key is not set to 3 the office application will not even try to load it on startup; Enable error alerts popups by configuring an environment variable SET VSTO_SUPPRESSDISPLAYALERTS=0 Enable logging errors to file by configuring an environment variable SET VSTO_LOGALERTS=1 Pray for an error alert popup or for an error in the log file so that you can fix its cause.  

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  • Installing Ubuntu One on Ubuntu 11.10 server

    - by Yar
    I have installed "Ubuntu One" on an Ubuntu server 11.10 based on these instructions: How do I configure Ubuntu one on a 11.10 server? Everything went smooth during installation. However when I try the command: u1sdtool --start to get the server up, I get the following stack error: u1sdtool --start /usr/lib/python2.7/dist-packages/gtk-2.0/gtk/init.py:57: GtkWarning: could not open display warnings.warn(str(e), _gtk.Warning) Unhandled Error Traceback (most recent call last): dbus.exceptions.DBusException: org.freedesktop.DBus.Error.NotSupported: Unable to autolaunch a dbus-daemon without a $DISPLAY for X11 Does anyone have a clue how to solve this issue?

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  • Installing Ubuntu One on Ubuntu 11.10 server

    - by Yaron
    I have installed "Ubuntu One" on an Ubuntu server 11.10 based on these instructions: How do I configure Ubuntu one on a 11.10 server? Everything went smooth during installation. However when I try the command: u1sdtool --start to get the server up, I get the following stack error: u1sdtool --start /usr/lib/python2.7/dist-packages/gtk-2.0/gtk/init.py:57: GtkWarning: could not open display warnings.warn(str(e), _gtk.Warning) Unhandled Error Traceback (most recent call last): dbus.exceptions.DBusException: org.freedesktop.DBus.Error.NotSupported: Unable to autolaunch a dbus-daemon without a $DISPLAY for X11 Does anyone have a clue how to solve this issue?

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  • 3dsmax crashes when exporting

    - by odoc
    I'm trying to export a (.max) file to openCOLLADA (.dae). Whenever I do this, 3dsmax crashes and produces this error: An error has occurred and the application will now close. No scene changes have occurred since your last save. 3dsmax then crashes but the COLLADA file is still produced. Whenever I try opening this COLLADA file in other software though, it comes up with a bad mesh data error. This is leading me to think that it wasn't exported correctly out of 3dsmax. Any advice?

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  • NVIDIA graphics driver on Macbook Pro 10,1

    - by Boatzart
    I just installed 14.04 over my old 12.04 partition on my Macbook Pro 10,1 (which is dual-booting with OS X) by following the instructions here. The only difference is that I'm using rEFInd instead of rEFIt. The proprietary NVIDIA drivers worked great with 12.04, but now I'm unable to boot into Unity with it in 14.04. Generally, I just get a black screen after the Grub menu, though occasionally I get some kind of panic screen like this, where I see errors like: [drm: __gen6_gt_force_wake_mt_get] *ERROR* Timed out waiting for forcewake old ack to clear. [drm: __gen6_gt_wait_for_thread_c0] *ERROR* GT thread status wait timed out [drm: __intel_ring_setup_status_page] *ERROR* render ring: wait for SyncFlush to complete for TLB invalidation timed out etc. Using the nouveau drivers works fine, but everything feels sluggish so I would really like to get the NVIDIA drivers working. Has anyone successfully gotten the NVIDIA drivers working with the GT-650M Mac Edition?

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