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  • C++ template specialization

    - by user231536
    I have a class template <typename T> class C { static const int K=1; static ostream& print(ostream& os, const T& t) { return os << t;} }; I would like to specialize C for int. //specialization for int template <> C<int>{ static const int K=2; } I want the default print method that works for int to remain and just change the constant. For some specializations, I want to keep K=1 and change the print method because there is no << operator. How do I do this?

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  • How to add visible menu item from php code (drupal)

    - by uta
    I have a content type with important "created" date field. And I have a menu link (in primary links) which is link to page that shows list of all nodes of my content type. (http://example.com/mycontenttype) I want to have menu links (visible in primary links) to each year when nodes of my content type are displayed (http://example.com/mycontenttype/2010). And I want to add these menu links from mymodule_nodeapi function, when the node is creating and only if it has a "created" date of new year. I know that I can create a pathes in mymodule_menu function, but it doesn't create a visible menu item. (Maybe I can somehow set parent_link_id or something else to do it?)

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  • how to export a 2D table in java

    - by kate
    hello i would like to ask you about the 2D tables in java!!my code is this an i would like to make a system out in order t see the registrations in mytable citylink can anyone help me? int i=0; while(i<=citylink.length){ for(Xml polh_is:fetchsite.child("site").child("poleis").children("polh")){ //url if((polh_is.string("name")=="")||(polh_is.content()==""))//attribute error += "Error in polh: name is - " + polh_is.string("name") + " with url - " + polh_is.content() + " -.\n"; else for(int j=0; j<citylink.length; j++){ citylink[j][0]=HtmlMethods.removeBreaks(polh_is.string("name")); citylink[j][1]=HtmlMethods.removeBreaks(polh_is.string("with url -"+polh_is.content() +"-.\n")); i++; } }

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  • CodeContracts: Possibly calling a method on a null reference

    - by dtb
    I'm having an argument with the CodeContracts static analysis tool. My code: class Foo { private static Foo instance = new Foo(); private string bar; public Foo() { bar = "Hello World"; } public static int BarLength() { return instance.bar.Length; // <<-- } } The tool tells me that instance.bar may be a null reference. I believe the opposite. Who is right? How can I prove it wrong?

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  • how toaccess the attributes in another form? c#

    - by Chelsea_cole
    I have a problem in a same namespace: public partial class frmForm1 : Form // Form1 { public class Account { public string Username; public string Password; } public class ListAcc { public static int count = 0; private static List<Account> UserList; public static List<Account> Data() { return UserList; } } } public partial class frmForm2 : Form // Form2 { private void button2_Click(object sender, EventArgs e) { frmForm1.Account A; string m = frmForm1.ListAcc<A>.[0].Username; //ERROR } } How could i access the attributes (Username, Password...) in frmForm1? Someone help me? Thanks!

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  • Contents of a node in Nokogiri

    - by Styggentorsken
    Is there a way to select all the contents of a node in Nokogiri? <root> <element>this is <hi>the content</hi> of my æøå element</element> </root> The result of getting the content of /root/element should be this is <hi>the content</hi> of my æøå element Edit: It seems like the solution is simply to use myElement.inner_html(). The problem I had was in fact that I was relying on an old version of libxml2, which escaped all the special characters.

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  • C++ Inheritance Question

    - by shaz
    I have a base class MessageHandler and 2 derived classes, MessageHandler_CB and MessageHandler_DQ. The derived classes redefine the handleMessage(...) method. MH_DQ processes a message and puts the result in a deque while MH_CB processes the message and then executes a callback function. The base class has a static callback function that I pass along with a this pointer to a library which calls the static callback when a new message is available for processing. My problem comes when I am in the static callback with a void * pointing to either a MH_DQ or a MH_CB. If I cast it to the base class the empty MessageHandler::handleMessage(...) method is called, rather than the version in the appropriate derived class. What is the best way to address this situation from a design perspective and/or what language features might help me to implement a solution to my problem? Thanks in advance!

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  • Django development server serving css but not js

    - by Wisco crew
    I am developing a django (1.4) app on my local machine. I am running the built-in development server with python manage.py runserver. In base.html I have: <link href="{{ STATIC_URL }}bootstrap.css" rel="stylesheet" type="text/css" /> <script src="{{ STATIC_URL }}boostrap-dropdown.js" type="text/javascript"></script> boostrap.css loads just fine when I load a page, but bootstrap-dropdown.js is 404'd. They are sitting right next to each other in my static directory. Relevant parts of settings.py: STATIC_URL = '/static/' STATICFILES_DIRS = ( '/home/username/projects/projectname/static',) Debug is set to True. I have tried it both with and without the staticfiles_urlpatterns trick. Django can find one file in the directory but not the other? I think I'm going crazy.

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  • Windows Phone 7 Control Caching - 'Element is already the child of another element'

    - by will
    I'm trying to speed up my windows phone 7 page load times. I have a 'static' page that has a dynamically created in a Panorama control - static meaning that the content never changes. On the first load I look at my config file, create the individual PanoramaItem controls and add them to the main Panorama control. I'm trying to keep a List in a static place so that the initial creation would only happen once and I could just add a fully rendered version to my Panorama control when the page was rendered. Works fine on first load, but when I try to add the cached PanoramaItems to the Panorama control I get the message "Element is already the child of another element". This makes sense since I already added before. But I can see a way to disconnect the PanoramaItems with the first Panorama control... I could be going about the control caching thing all wrong as well... Let me know if there's another way to do this.

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  • jQuery accordion expanded

    - by hajder
    I am trying to create an accordion with jQuery from this example http://docs.jquery.com/UI/Accordion The markup is the same, i.e. <div id="accordion"> <h3><a href="#">First header</a></h3> <div>First content</div> <h3><a href="#">Second header</a></h3> <div>Second content</div> </div> And I have script file enqueued correctly, which has the following content: $ = jQuery; $(document).ready(function() { $("#accordion").accordion(); }); But I get this error in the console output TypeError: 'undefined' is not a function (evaluating '$("#accordion").accordion()') The result being all divs are expanded, i.e not clickable.

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  • php define variable inside str_replace array

    - by john
    I have a template system, that replaces text such as {HEADER} with the appropriate content. I use an array like this, that replaces the key with the value using str_replace. $array = array("HEADER","This is the header"); foreach($array as $var => $content) { $template = str_replace("{" . strtoupper($var). "}", $content,$template); } Now im trying to use a defined variable like this: define("NAME","Site Name"); Inside the value for the header. So I want the defined variable to be inside the array which gets replaced so it would look like this, but it doesn't work. $array = array("HEADER","Welcome to ".NAME."'s website!"); Any ideas? tell me if im not clear

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  • Personalize Diff Command in Ubuntu

    - by acidboy
    I have two files, both with a lot of data, what I need is compare the first word of each file (each file always starts with a number, and each number could have many digits). The files are identical when these numbers are the same. Example: I have 3 files: a.txt, b.txt and c.txt a.txt content is "1 a b c 3 5 6 hjkj" b.txt content is "1 c f a 1234 h" c.txt content is "2 a b c 3 5 6 hjkj" diff a.txt b.txt should return "files are identical" diff a.txt c.txt should return "files are different" How can I compare them using the diff command?

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  • how to format (css) data loaded with $.load or $.get or $.ajax?

    - by user356981
    I need to load a piece of content html when an link in a menu is clicked; once loaded, the css format is not working properly, how do I re-format (re-styling via css) the loaded code? My code is: $('a', mainMenu).click(function() { ref = this.href; $('#content').load(ref + ' #content' function() { url = '../css/jquery-ui-1.8.2.custom.css'; //styling here if (document.createStyleSheet) document.createStyleSheet(url); else $('<link rel="stylesheet" type="text/css" href="'+url+'"/>').appendTo('head'); }); }) is it another way to load and re-style html (plugins perhaps)? thanks in adv'n.

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  • Singleton Creation preference

    - by cwieland
    You can create singletons in a variety of ways. I am wondering which is better between these. +(ServerConnection*)shared{ static dispatch_once_t pred=0; __strong static id _sharedObject = nil; dispatch_once(&pred, ^{ _sharedObject = [[self alloc] init]; // or some other init method }); return _sharedObject; } I could see that this compiles down to something very fast. I would think that checking the predicate would be another function call. The other is: +(ServerConnection*)shared{ static ServerConnection* connection=nil; if (connection==nil) { connection=[[ServerConnection alloc] init]; } return connection; } Are there any major differences between the two? I know these are probably similar enough to not worry about it. But Just wondering.

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  • Efficient implementation of exclusive execution

    - by n0weak
    I have an ObjectManager class that is used to process payments. It is wrapped over the Order entities, so new instance has to be created when processing is required. I need to prevent the situation when several ObjectManager instances are dealing with the same order simultaneously (it happend once because of some errors on the remote payment processing center, somehow they called our callback urls twice). I'd love to get an advice how to implement it more efficiently. For now, I am thinking about something like that: public class OrderManager{ private static final CopyOnWriteArrayList<Integer> LOCKER = new CopyOnWriteArrayList<Integer>(); private static synchronized boolean tryLock(Integer key) { return LOCKER.addIfAbsent(key); } private static void releaseLock(Integer key) { LOCKER.remove(key); } public void processPayment(Integer orderId) throws Exception{ if (!tryLock(orderId)) { return; } try { //operate } finally { releaseLock(orderId); } } //remainder omitted }

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  • IE 8 and jquery problem

    - by Hellnar
    I have such div: <div class="box"> <div id="myid" style="display:hidden;"> <p>some stuff here</p></div> </div> when I do $("myid").slideToggle("slow"); , if the content of has bigger height over box, my content overflows from the bottom of the "box" class, weirdly this doesn't happen with other browsers but IE8 How can I fix this issue so that when "myid" starts to display content, height of the .box resizes itself to fit the inner div.

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  • Non-floated div drops below right floated div in IE9 (and 7)

    - by PVA
    This is a responsive site, (http://www.dermatologypartners.com) with desktop styles first. IE8 handles the pages correctly, though without CSS3 flourishes. But IE9 is dropping my navbar (on left) down, when it is up next to the right floated content in all the other browsers. My navbar is near the end of the HTML because I want it to flow over LAST, below page content but above the footer, in the smartphone version of the site -- which it does. The nav is NOT floated. It just rises to the top left and content is floated to the right. Except in IE9. I don't to have to redo all this, if I can just get an IE9 fix. It's not "float drop" - there's plenty of room available. I'm actually having the same problem in IE7, but I'm not concerned with IE7 -- but why 7 & 9, while 8 is fine? Thanks!

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  • I can't upload a file with CGIHTTPServer

    - by sdemingo
    Hi all, I'm using the CGIHTTPServer to implement a simple cgi server. I'm trying to upload a file by a form with the post method and the multipart/form-data enctype but I have problems when I recover the value of the fields in the cgi script. When the script catch the form fields, the value of the file is a MiniFieldStorage with two fields only (key and file name), and I can't recover the content of the file. As the API doc shows, this content is in value field of a StorageField but in the MiniFieldStorage this field isn't exits. ¿How can I recover a StorageField with the content of the file instead a MiniStorageField? ¿There are other method to upload a file using CGIHTTPServer? Thanks a lot

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  • AJAX or full page reload

    - by wh0
    I have a simple web page with top navigation and the content, on click of a certain link in top navigation content changes accordingly. Now my question is should do it using AJAX call and load the HTML it into content or should i reload the entire page.It is small page fetching data does not take much of the time but i wonder approach is better suited and why ? My opinion is AJAX way, but some of the web pages that i have seen goes for full page reload i wonder why. i'm not sure AJAX method it has any cons in it. Can someone please elaborate this for me.

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  • Rough Animation

    - by nate8684
    Anyone know why the animation is rough (doesn't really animate) on this bit of jquery? $('.close').click(function() { $('.hidden-content').fadeOut('fast', function (){ $('.serv-button').fadeIn('fast'); }); }); Basically when you click on the close button a ".hidden-content" should fade out and the "serv-button"'s should fade in. But instead they just appear and do no fade. Here is my working example, it's on the services section: http://www.hdesignonline.com/qdup/ Basically I need the content to fade out exactly how it fades in...

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  • Espeak SAPI/dll usage on Windows ?

    - by Quandary
    Question: I am trying to use the espeak text-to-speech engine. So for I got it working wounderfully on linux (code below). Now I wanted to port this basic program to windows, too, but it's nearly impossible... Part of the problem is that the windows dll only allows for AUDIO_OUTPUT_SYNCHRONOUS, which means it requires a callback, but I can't figure out how to play the audio from the callback... First it crashed, then I realized, I need a callback function, now I get the data in the callback function, but I don't know how to play it... as it is neither a wav file nor plays automatically as on Linux. The sourceforge site is rather useless, because it basically says use the SAPI version, but then there is no example on how to use the sapi espeak dll... Anyway, here's my code, can anybody help? #ifdef __cplusplus #include <cstdio> #include <cstdlib> #include <cstring> else #include <stdio.h> #include <stdlib.h> #include <string.h> endif include include //#include "speak_lib.h" include "espeak/speak_lib.h" // libespeak-dev: /usr/include/espeak/speak_lib.h // apt-get install libespeak-dev // apt-get install libportaudio-dev // g++ -o mine mine.cpp -lespeak // g++ -o mine mine.cpp -I/usr/include/espeak/ -lespeak // gcc -o mine mine.cpp -I/usr/include/espeak/ -lespeak char voicename[40]; int samplerate; int quiet = 0; static char genders[4] = {' ','M','F',' '}; //const char *data_path = "/usr/share/"; // /usr/share/espeak-data/ const char *data_path = NULL; // use default path for espeak-data int strrcmp(const char *s, const char *sub) { int slen = strlen(s); int sublen = strlen(sub); return memcmp(s + slen - sublen, sub, sublen); } char * strrcpy(char *dest, const char *source) { // Pre assertions assert(dest != NULL); assert(source != NULL); assert(dest != source); // tk: parentheses while((*dest++ = *source++)) ; return(--dest); } const char* GetLanguageVoiceName(const char* pszShortSign) { #define LANGUAGE_LENGTH 30 static char szReturnValue[LANGUAGE_LENGTH] ; memset(szReturnValue, 0, LANGUAGE_LENGTH); for (int i = 0; pszShortSign[i] != '\0'; ++i) szReturnValue[i] = (char) tolower(pszShortSign[i]); const espeak_VOICE **voices; espeak_VOICE voice_select; voices = espeak_ListVoices(NULL); const espeak_VOICE *v; for(int ix=0; (v = voices[ix]) != NULL; ix++) { if( !strrcmp( v->languages, szReturnValue) ) { strcpy(szReturnValue, v->name); return szReturnValue; } } // End for strcpy(szReturnValue, "default"); return szReturnValue; } // End function getvoicename void ListVoices() { const espeak_VOICE **voices; espeak_VOICE voice_select; voices = espeak_ListVoices(NULL); const espeak_VOICE *v; for(int ix=0; (v = voices[ix]) != NULL; ix++) { printf("Shortsign: %s\n", v->languages); printf("age: %d\n", v->age); printf("gender: %c\n", genders[v->gender]); printf("name: %s\n", v->name); printf("\n\n"); } // End for } // End function getvoicename int main() { printf("Hello World!\n"); const char* szVersionInfo = espeak_Info(NULL); printf("Espeak version: %s\n", szVersionInfo); samplerate = espeak_Initialize(AUDIO_OUTPUT_PLAYBACK,0,data_path,0); strcpy(voicename, "default"); // espeak --voices strcpy(voicename, "german"); strcpy(voicename, GetLanguageVoiceName("DE")); if(espeak_SetVoiceByName(voicename) != EE_OK) { printf("Espeak setvoice error...\n"); } static char word[200] = "Hello World" ; strcpy(word, "TV-fäns aufgepasst, es ist 20 Uhr 15. Zeit für Rambo 3"); strcpy(word, "Unnamed Player wurde zum Opfer von GSG9"); int speed = 220; int volume = 500; // volume in range 0-100 0=silence int pitch = 50; // base pitch, range 0-100. 50=normal // espeak.cpp 625 espeak_SetParameter(espeakRATE, speed, 0); espeak_SetParameter(espeakVOLUME,volume,0); espeak_SetParameter(espeakPITCH,pitch,0); // espeakRANGE: pitch range, range 0-100. 0-monotone, 50=normal // espeakPUNCTUATION: which punctuation characters to announce: // value in espeak_PUNCT_TYPE (none, all, some), espeak_VOICE *voice_spec = espeak_GetCurrentVoice(); voice_spec->gender=2; // 0=none 1=male, 2=female, //voice_spec->age = age; espeak_SetVoiceByProperties(voice_spec); espeak_Synth( (char*) word, strlen(word)+1, 0, POS_CHARACTER, 0, espeakCHARS_AUTO, NULL, NULL); espeak_Synchronize(); strcpy(voicename, GetLanguageVoiceName("EN")); espeak_SetVoiceByName(voicename); strcpy(word, "Geany was fragged by GSG9 Googlebot"); strcpy(word, "Googlebot"); espeak_Synth( (char*) word, strlen(word)+1, 0, POS_CHARACTER, 0, espeakCHARS_AUTO, NULL, NULL); espeak_Synchronize(); espeak_Terminate(); printf("Espeak terminated\n"); return EXIT_SUCCESS; } /* if(espeak_SetVoiceByName(voicename) != EE_OK) { memset(&voice_select,0,sizeof(voice_select)); voice_select.languages = voicename; if(espeak_SetVoiceByProperties(&voice_select) != EE_OK) { fprintf(stderr,"%svoice '%s'\n",err_load,voicename); exit(2); } } */ The above code is for Linux. The below code is about as far as I got on Vista x64 (32 bit emu): #ifdef __cplusplus #include <cstdio> #include <cstdlib> #include <cstring> else #include <stdio.h> #include <stdlib.h> #include <string.h> endif include include include "speak_lib.h" //#include "espeak/speak_lib.h" // libespeak-dev: /usr/include/espeak/speak_lib.h // apt-get install libespeak-dev // apt-get install libportaudio-dev // g++ -o mine mine.cpp -lespeak // g++ -o mine mine.cpp -I/usr/include/espeak/ -lespeak // gcc -o mine mine.cpp -I/usr/include/espeak/ -lespeak char voicename[40]; int iSampleRate; int quiet = 0; static char genders[4] = {' ','M','F',' '}; //const char *data_path = "/usr/share/"; // /usr/share/espeak-data/ //const char *data_path = NULL; // use default path for espeak-data const char *data_path = "C:\Users\Username\Desktop\espeak-1.43-source\espeak-1.43-source\"; int strrcmp(const char *s, const char *sub) { int slen = strlen(s); int sublen = strlen(sub); return memcmp(s + slen - sublen, sub, sublen); } char * strrcpy(char *dest, const char *source) { // Pre assertions assert(dest != NULL); assert(source != NULL); assert(dest != source); // tk: parentheses while((*dest++ = *source++)) ; return(--dest); } const char* GetLanguageVoiceName(const char* pszShortSign) { #define LANGUAGE_LENGTH 30 static char szReturnValue[LANGUAGE_LENGTH] ; memset(szReturnValue, 0, LANGUAGE_LENGTH); for (int i = 0; pszShortSign[i] != '\0'; ++i) szReturnValue[i] = (char) tolower(pszShortSign[i]); const espeak_VOICE **voices; espeak_VOICE voice_select; voices = espeak_ListVoices(NULL); const espeak_VOICE *v; for(int ix=0; (v = voices[ix]) != NULL; ix++) { if( !strrcmp( v->languages, szReturnValue) ) { strcpy(szReturnValue, v->name); return szReturnValue; } } // End for strcpy(szReturnValue, "default"); return szReturnValue; } // End function getvoicename void ListVoices() { const espeak_VOICE **voices; espeak_VOICE voice_select; voices = espeak_ListVoices(NULL); const espeak_VOICE *v; for(int ix=0; (v = voices[ix]) != NULL; ix++) { printf("Shortsign: %s\n", v->languages); printf("age: %d\n", v->age); printf("gender: %c\n", genders[v->gender]); printf("name: %s\n", v->name); printf("\n\n"); } // End for } // End function getvoicename /* Callback from espeak. Directly speaks using AudioTrack. */ define LOGI(x) printf("%s\n", x) static int AndroidEspeakDirectSpeechCallback(short *wav, int numsamples, espeak_EVENT *events) { char buf[100]; sprintf(buf, "AndroidEspeakDirectSpeechCallback: %d samples", numsamples); LOGI(buf); if (wav == NULL) { LOGI("Null: speech has completed"); } if (numsamples > 0) { //audout->write(wav, sizeof(short) * numsamples); sprintf(buf, "AudioTrack wrote: %d bytes", sizeof(short) * numsamples); LOGI(buf); } return 0; // continue synthesis (1 is to abort) } static int AndroidEspeakSynthToFileCallback(short *wav, int numsamples,espeak_EVENT *events) { char buf[100]; sprintf(buf, "AndroidEspeakSynthToFileCallback: %d samples", numsamples); LOGI(buf); if (wav == NULL) { LOGI("Null: speech has completed"); } // The user data should contain the file pointer of the file to write to //void* user_data = events->user_data; FILE* user_data = fopen ( "myfile1.wav" , "ab" ); FILE* fp = static_cast<FILE *>(user_data); // Write all of the samples fwrite(wav, sizeof(short), numsamples, fp); return 0; // continue synthesis (1 is to abort) } int main() { printf("Hello World!\n"); const char* szVersionInfo = espeak_Info(NULL); printf("Espeak version: %s\n", szVersionInfo); iSampleRate = espeak_Initialize(AUDIO_OUTPUT_SYNCHRONOUS, 4096, data_path, 0); if (iSampleRate <= 0) { printf("Unable to initialize espeak"); return EXIT_FAILURE; } //samplerate = espeak_Initialize(AUDIO_OUTPUT_PLAYBACK,0,data_path,0); //ListVoices(); strcpy(voicename, "default"); // espeak --voices //strcpy(voicename, "german"); //strcpy(voicename, GetLanguageVoiceName("DE")); if(espeak_SetVoiceByName(voicename) != EE_OK) { printf("Espeak setvoice error...\n"); } static char word[200] = "Hello World" ; strcpy(word, "TV-fäns aufgepasst, es ist 20 Uhr 15. Zeit für Rambo 3"); strcpy(word, "Unnamed Player wurde zum Opfer von GSG9"); int speed = 220; int volume = 500; // volume in range 0-100 0=silence int pitch = 50; // base pitch, range 0-100. 50=normal // espeak.cpp 625 espeak_SetParameter(espeakRATE, speed, 0); espeak_SetParameter(espeakVOLUME,volume,0); espeak_SetParameter(espeakPITCH,pitch,0); // espeakRANGE: pitch range, range 0-100. 0-monotone, 50=normal // espeakPUNCTUATION: which punctuation characters to announce: // value in espeak_PUNCT_TYPE (none, all, some), //espeak_VOICE *voice_spec = espeak_GetCurrentVoice(); //voice_spec->gender=2; // 0=none 1=male, 2=female, //voice_spec->age = age; //espeak_SetVoiceByProperties(voice_spec); //espeak_SetSynthCallback(AndroidEspeakDirectSpeechCallback); espeak_SetSynthCallback(AndroidEspeakSynthToFileCallback); unsigned int unique_identifier; espeak_ERROR err = espeak_Synth( (char*) word, strlen(word)+1, 0, POS_CHARACTER, 0, espeakCHARS_AUTO, &unique_identifier, NULL); err = espeak_Synchronize(); /* strcpy(voicename, GetLanguageVoiceName("EN")); espeak_SetVoiceByName(voicename); strcpy(word, "Geany was fragged by GSG9 Googlebot"); strcpy(word, "Googlebot"); espeak_Synth( (char*) word, strlen(word)+1, 0, POS_CHARACTER, 0, espeakCHARS_AUTO, NULL, NULL); espeak_Synchronize(); */ // espeak_Cancel(); espeak_Terminate(); printf("Espeak terminated\n"); system("pause"); return EXIT_SUCCESS; }

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  • JSON error Caused by: java.lang.NullPointerException

    - by user3821853
    im trying to make a register page on android using JSON. everytime i press register button on avd, i get an error "unfortunately database has stopped". i have a error on my logcat that i cannot understand. this my code. please someone help me. this my register.java import android.app.Activity; import android.app.ProgressDialog; import android.os.AsyncTask; import android.os.Bundle; import android.util.Log; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; import android.widget.EditText; import android.widget.Toast; import org.apache.http.NameValuePair; import org.apache.http.message.BasicNameValuePair; import org.json.JSONException; import org.json.JSONObject; import java.util.ArrayList; import java.util.List; public class Register extends Activity implements OnClickListener{ private EditText user, pass; private Button mRegister; // Progress Dialog private ProgressDialog pDialog; // JSON parser class JSONParser jsonParser = new JSONParser(); //php register script //localhost : //testing on your device //put your local ip instead, on windows, run CMD > ipconfig //or in mac's terminal type ifconfig and look for the ip under en0 or en1 // private static final String REGISTER_URL = "http://xxx.xxx.x.x:1234/webservice/register.php"; //testing on Emulator: private static final String REGISTER_URL = "http://10.0.2.2:1234/webservice/register.php"; //testing from a real server: //private static final String REGISTER_URL = "http://www.mybringback.com/webservice/register.php"; //ids private static final String TAG_SUCCESS = "success"; private static final String TAG_MESSAGE = "message"; @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); setContentView(R.layout.register); user = (EditText)findViewById(R.id.username); pass = (EditText)findViewById(R.id.password); mRegister = (Button)findViewById(R.id.register); mRegister.setOnClickListener(this); } @Override public void onClick(View v) { // TODO Auto-generated method stub new CreateUser().execute(); } class CreateUser extends AsyncTask<String, String, String> { @Override protected void onPreExecute() { super.onPreExecute(); pDialog = new ProgressDialog(Register.this); pDialog.setMessage("Creating User..."); pDialog.setIndeterminate(false); pDialog.setCancelable(true); pDialog.show(); } @Override protected String doInBackground(String... args) { // TODO Auto-generated method stub // Check for success tag int success; String username = user.getText().toString(); String password = pass.getText().toString(); try { // Building Parameters List<NameValuePair> params = new ArrayList<NameValuePair>(); params.add(new BasicNameValuePair("username", username)); params.add(new BasicNameValuePair("password", password)); Log.d("request!", "starting"); //Posting user data to script JSONObject json = jsonParser.makeHttpRequest( REGISTER_URL, "POST", params); // full json response Log.d("Registering attempt", json.toString()); // json success element success = json.getInt(TAG_SUCCESS); if (success == 1) { Log.d("User Created!", json.toString()); finish(); return json.getString(TAG_MESSAGE); }else{ Log.d("Registering Failure!", json.getString(TAG_MESSAGE)); return json.getString(TAG_MESSAGE); } } catch (JSONException e) { e.printStackTrace(); } return null; } protected void onPostExecute(String file_url) { // dismiss the dialog once product deleted pDialog.dismiss(); if (file_url != null){ Toast.makeText(Register.this, file_url, Toast.LENGTH_LONG).show(); } } } } this is JSONparser.java import android.util.Log; import org.apache.http.HttpEntity; import org.apache.http.HttpResponse; import org.apache.http.NameValuePair; import org.apache.http.client.ClientProtocolException; import org.apache.http.client.entity.UrlEncodedFormEntity; import org.apache.http.client.methods.HttpGet; import org.apache.http.client.methods.HttpPost; import org.apache.http.client.utils.URLEncodedUtils; import org.apache.http.impl.client.DefaultHttpClient; import org.json.JSONException; import org.json.JSONObject; import java.io.BufferedReader; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader; import java.io.UnsupportedEncodingException; import java.util.List; public class JSONParser { static InputStream is = null; static JSONObject jObj = null; static String json = ""; // constructor public JSONParser() { } public JSONObject getJSONFromUrl(final String url) { // Making HTTP request try { // Construct the client and the HTTP request. DefaultHttpClient httpClient = new DefaultHttpClient(); HttpPost httpPost = new HttpPost(url); // Execute the POST request and store the response locally. HttpResponse httpResponse = httpClient.execute(httpPost); // Extract data from the response. HttpEntity httpEntity = httpResponse.getEntity(); // Open an inputStream with the data content. is = httpEntity.getContent(); } catch (UnsupportedEncodingException e) { e.printStackTrace(); } catch (ClientProtocolException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } try { // Create a BufferedReader to parse through the inputStream. BufferedReader reader = new BufferedReader(new InputStreamReader( is, "iso-8859-1"), 8); // Declare a string builder to help with the parsing. StringBuilder sb = new StringBuilder(); // Declare a string to store the JSON object data in string form. String line = null; // Build the string until null. while ((line = reader.readLine()) != null) { sb.append(line + "\n"); } // Close the input stream. is.close(); // Convert the string builder data to an actual string. json = sb.toString(); } catch (Exception e) { Log.e("Buffer Error", "Error converting result " + e.toString()); } // Try to parse the string to a JSON object try { jObj = new JSONObject(json); } catch (JSONException e) { Log.e("JSON Parser", "Error parsing data " + e.toString()); } // Return the JSON Object. return jObj; } // function get json from url // by making HTTP POST or GET mehtod public JSONObject makeHttpRequest(String url, String method, List<NameValuePair> params) { // Making HTTP request try { // check for request method if(method == "POST"){ // request method is POST // defaultHttpClient DefaultHttpClient httpClient = new DefaultHttpClient(); HttpPost httpPost = new HttpPost(url); httpPost.setEntity(new UrlEncodedFormEntity(params)); HttpResponse httpResponse = httpClient.execute(httpPost); HttpEntity httpEntity = httpResponse.getEntity(); is = httpEntity.getContent(); }else if(method == "GET"){ // request method is GET DefaultHttpClient httpClient = new DefaultHttpClient(); String paramString = URLEncodedUtils.format(params, "utf-8"); url += "?" + paramString; HttpGet httpGet = new HttpGet(url); HttpResponse httpResponse = httpClient.execute(httpGet); HttpEntity httpEntity = httpResponse.getEntity(); is = httpEntity.getContent(); } } catch (UnsupportedEncodingException e) { e.printStackTrace(); } catch (ClientProtocolException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } try { BufferedReader reader = new BufferedReader(new InputStreamReader( is, "iso-8859-1"), 8); StringBuilder sb = new StringBuilder(); String line = null; while ((line = reader.readLine()) != null) { sb.append(line + "\n"); } is.close(); json = sb.toString(); } catch (Exception e) { Log.e("Buffer Error", "Error converting result " + e.toString()); } // try parse the string to a JSON object try { jObj = new JSONObject(json); } catch (JSONException e) { Log.e("JSON Parser", "Error parsing data " + e.toString()); } // return JSON String return jObj; } } and this my error 08-18 23:40:02.381 2000-2018/com.example.blackcustomzier.database E/Buffer Error? Error converting result java.lang.NullPointerException: lock == null 08-18 23:40:02.381 2000-2018/com.example.blackcustomzier.database E/JSON Parser? Error parsing data org.json.JSONException: End of input at character 0 of 08-18 23:40:02.391 2000-2018/com.example.blackcustomzier.database W/dalvikvm? threadid=15: thread exiting with uncaught exception (group=0xb0f37648) 08-18 23:40:02.391 2000-2018/com.example.blackcustomzier.database E/AndroidRuntime? FATAL EXCEPTION: AsyncTask #4 java.lang.RuntimeException: An error occured while executing doInBackground() at android.os.AsyncTask$3.done(AsyncTask.java:299) at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:352) at java.util.concurrent.FutureTask.setException(FutureTask.java:219) at java.util.concurrent.FutureTask.run(FutureTask.java:239) at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1080) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:573) at java.lang.Thread.run(Thread.java:841) Caused by: java.lang.NullPointerException at com.example.blackcustomzier.database.Register$CreateUser.doInBackground(Register.java:108) at com.example.blackcustomzier.database.Register$CreateUser.doInBackground(Register.java:74) at android.os.AsyncTask$2.call(AsyncTask.java:287) at java.util.concurrent.FutureTask.run(FutureTask.java:234)             at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230)             at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1080)             at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:573)             at java.lang.Thread.run(Thread.java:841) 08-18 23:40:02.501 2000-2000/com.example.blackcustomzier.database W/EGL_emulation? eglSurfaceAttrib not implemented 08-18 23:40:02.591 2000-2000/com.example.blackcustomzier.database W/EGL_emulation? eglSurfaceAttrib not implemented 08-18 23:40:02.981 2000-2000/com.example.blackcustomzier.database E/WindowManager? Activity com.example.blackcustomzier.database.Register has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView{b1294c60 V.E..... R......D 0,0-1026,288} that was originally added here android.view.WindowLeaked: Activity com.example.blackcustomzier.database.Register has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView{b1294c60 V.E..... R......D 0,0-1026,288} that was originally added here at android.view.ViewRootImpl.<init>(ViewRootImpl.java:345) at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:239) at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:69) at android.app.Dialog.show(Dialog.java:281) at com.example.blackcustomzier.database.Register$CreateUser.onPreExecute(Register.java:85) at android.os.AsyncTask.executeOnExecutor(AsyncTask.java:586) at android.os.AsyncTask.execute(AsyncTask.java:534) at com.example.blackcustomzier.database.Register.onClick(Register.java:70) at android.view.View.performClick(View.java:4240) at android.view.View.onKeyUp(View.java:7928) at android.widget.TextView.onKeyUp(TextView.java:5606) at android.view.KeyEvent.dispatch(KeyEvent.java:2647) at android.view.View.dispatchKeyEvent(View.java:7343) at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1393) at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1393) at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1393) at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1393) at com.android.internal.policy.impl.PhoneWindow$DecorView.superDispatchKeyEvent(PhoneWindow.java:1933) at com.android.internal.policy.impl.PhoneWindow.superDispatchKeyEvent(PhoneWindow.java:1408) at android.app.Activity.dispatchKeyEvent(Activity.java:2384) at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchKeyEvent(PhoneWindow.java:1860) at android.view.ViewRootImpl$ViewPostImeInputStage.processKeyEvent(ViewRootImpl.java:3791) at android.view.ViewRootImpl$ViewPostImeInputStage.onProcess(ViewRootImpl.java:3774) at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:3379) at android.view.ViewRootImpl$InputStage.onDeliverToNext(ViewRootImpl.java:3429) at android.view.ViewRootImpl$InputStage.forward(ViewRootImpl.java:3398) at android.view.ViewRootImpl$AsyncInputStage.forward(ViewRootImpl.java:3483) at android.view.ViewRootImpl$InputStage.apply(ViewRootImpl.java:3406) at android.view.ViewRootImpl$AsyncInputStage.apply(ViewRootImpl.java:3540) at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:3379) at android.view.ViewRootImpl$InputStage.onDeliverToNext(ViewRootImpl.java:3429) at android.view.ViewRootImpl$InputStage.forward(ViewRootImpl.java:3398) at android.view.ViewRootImpl$InputStage.apply(ViewRootImpl.java:3406) at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:3379) at android.view.ViewRootImpl$InputStage.onDeliverToNext(ViewRootImpl.java:3429) at android.view.ViewRootImpl$InputStage.forward(ViewRootImpl.java:3398) at android.view.ViewRootImpl$AsyncInputStage.forward(ViewRootImpl.java:3516) at android.view.ViewRootImpl$ImeInputStage.onFinishedInputEvent(ViewRootImpl.java:3666) at android.view.inputmethod.InputMethodManager$PendingEvent.run(InputMethodManager.java:1982) at android.view.inputmethod.InputMethodManager.invokeFinishedInputEventCallback(InputMethodManager.java:1698) at android.view.inputmethod.InputMethodManager.finishedInputEvent(InputMethodManager.java:1689) at android.view.inputmethod.InputMethodManager$ImeInputEventSender.onInputEventFinished(InputMethodManager.java:1959) at android.view.InputEventSender.dispatchInputEventFinished(InputEventSender.java:141) at android.os.MessageQueue.nativePollOnce(Native Method) at android.os.MessageQueue.next(MessageQueue.java:132) at android.os.Looper.loop(Looper.java:124) at android.app.ActivityThread.main(ActivityThread.java:5103) at java.lang.reflect.Method.invokeNative(Native Method) at java.lang.reflect.Method.invoke(Method.java:525) at com.android.internal.os.ZygoteInit$MethodAndArgsCal please help me to solve this thx

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  • C# 5 Async, Part 1: Simplifying Asynchrony – That for which we await

    - by Reed
    Today’s announcement at PDC of the future directions C# is taking excite me greatly.  The new Visual Studio Async CTP is amazing.  Asynchronous code – code which frustrates and demoralizes even the most advanced of developers, is taking a huge leap forward in terms of usability.  This is handled by building on the Task functionality in .NET 4, as well as the addition of two new keywords being added to the C# language: async and await. This core of the new asynchronous functionality is built upon three key features.  First is the Task functionality in .NET 4, and based on Task and Task<TResult>.  While Task was intended to be the primary means of asynchronous programming with .NET 4, the .NET Framework was still based mainly on the Asynchronous Pattern and the Event-based Asynchronous Pattern. The .NET Framework added functionality and guidance for wrapping existing APIs into a Task based API, but the framework itself didn’t really adopt Task or Task<TResult> in any meaningful way.  The CTP shows that, going forward, this is changing. One of the three key new features coming in C# is actually a .NET Framework feature.  Nearly every asynchronous API in the .NET Framework has been wrapped into a new, Task-based method calls.  In the CTP, this is done via as external assembly (AsyncCtpLibrary.dll) which uses Extension Methods to wrap the existing APIs.  However, going forward, this will be handled directly within the Framework.  This will have a unifying effect throughout the .NET Framework.  This is the first building block of the new features for asynchronous programming: Going forward, all asynchronous operations will work via a method that returns Task or Task<TResult> The second key feature is the new async contextual keyword being added to the language.  The async keyword is used to declare an asynchronous function, which is a method that either returns void, a Task, or a Task<T>. Inside the asynchronous function, there must be at least one await expression.  This is a new C# keyword (await) that is used to automatically take a series of statements and break it up to potentially use discontinuous evaluation.  This is done by using await on any expression that evaluates to a Task or Task<T>. For example, suppose we want to download a webpage as a string.  There is a new method added to WebClient: Task<string> WebClient.DownloadStringTaskAsync(Uri).  Since this returns a Task<string> we can use it within an asynchronous function.  Suppose, for example, that we wanted to do something similar to my asynchronous Task example – download a web page asynchronously and check to see if it supports XHTML 1.0, then report this into a TextBox.  This could be done like so: private async void button1_Click(object sender, RoutedEventArgs e) { string url = "http://reedcopsey.com"; string content = await new WebClient().DownloadStringTaskAsync(url); this.textBox1.Text = string.Format("Page {0} supports XHTML 1.0: {1}", url, content.Contains("XHTML 1.0")); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Let’s walk through what’s happening here, step by step.  By adding the async contextual keyword to the method definition, we are able to use the await keyword on our WebClient.DownloadStringTaskAsync method call. When the user clicks this button, the new method (Task<string> WebClient.DownloadStringTaskAsync(string)) is called, which returns a Task<string>.  By adding the await keyword, the runtime will call this method that returns Task<string>, and execution will return to the caller at this point.  This means that our UI is not blocked while the webpage is downloaded.  Instead, the UI thread will “await” at this point, and let the WebClient do it’s thing asynchronously. When the WebClient finishes downloading the string, the user interface’s synchronization context will automatically be used to “pick up” where it left off, and the Task<string> returned from DownloadStringTaskAsync is automatically unwrapped and set into the content variable.  At this point, we can use that and set our text box content. There are a couple of key points here: Asynchronous functions are declared with the async keyword, and contain one or more await expressions In addition to the obvious benefits of shorter, simpler code – there are some subtle but tremendous benefits in this approach.  When the execution of this asynchronous function continues after the first await statement, the initial synchronization context is used to continue the execution of this function.  That means that we don’t have to explicitly marshal the call that sets textbox1.Text back to the UI thread – it’s handled automatically by the language and framework!  Exception handling around asynchronous method calls also just works. I’d recommend every C# developer take a look at the documentation on the new Asynchronous Programming for C# and Visual Basic page, download the Visual Studio Async CTP, and try it out.

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  • Dynamic connection for LINQ to SQL DataContext

    - by Steve Clements
    If for some reason you need to specify a specific connection string for a DataContext, you can of course pass the connection string when you initialise you DataContext object.  A common scenario could be a dev/test/stage/live connection string, but in my case its for either a live or archive database.   I however want the connection string to be handled by the DataContext, there are probably lots of different reasons someone would want to do this…but here are mine. I want the same connection string for all instances of DataContext, but I don’t know what it is yet! I prefer the clean code and ease of not using a constructor parameter. The refactoring of using a constructor parameter could be a nightmare.   So my approach is to create a new partial class for the DataContext and handle empty constructor in there. First from within the LINQ to SQL designer I changed the connection property to None.  This will remove the empty constructor code from the auto generated designer.cs file. Right click on the .dbml file, click View Code and a file and class is created for you! You’ll see the new class created in solutions explorer and the file will open. We are going to be playing with constructors so you need to add the inheritance from System.Data.Linq.DataContext public partial class DataClasses1DataContext : System.Data.Linq.DataContext    {    }   Add the empty constructor and I have added a property that will get my connection string, you will have whatever logic you need to decide and get the connection string you require.  In my case I will be hitting a database, but I have omitted that code. public partial class DataClasses1DataContext : System.Data.Linq.DataContext {    // Connection String Keys - stored in web.config    static string LiveConnectionStringKey = "LiveConnectionString";    static string ArchiveConnectionStringKey = "ArchiveConnectionString";      protected static string ConnectionString    {       get       {          if (DoIWantToUseTheLiveConnection) {             return global::System.Configuration.ConfigurationManager.ConnectionStrings[LiveConnectionStringKey].ConnectionString;          }          else {             return global::System.Configuration.ConfigurationManager.ConnectionStrings[ArchiveConnectionStringKey].ConnectionString;          }       }    }      public DataClasses1DataContext() :       base(ConnectionString, mappingSource)    {       OnCreated();    } }   Now when I new up my DataContext, I can just leave the constructor empty and my partial class will decide which one i need to use. Nice, clean code that can be easily refractored and tested.   Share this post :

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  • Using jQuery to POST Form Data to an ASP.NET ASMX AJAX Web Service

    - by Rick Strahl
    The other day I got a question about how to call an ASP.NET ASMX Web Service or PageMethods with the POST data from a Web Form (or any HTML form for that matter). The idea is that you should be able to call an endpoint URL, send it regular urlencoded POST data and then use Request.Form[] to retrieve the posted data as needed. My first reaction was that you can’t do it, because ASP.NET ASMX AJAX services (as well as Page Methods and WCF REST AJAX Services) require that the content POSTed to the server is posted as JSON and sent with an application/json or application/x-javascript content type. IOW, you can’t directly call an ASP.NET AJAX service with regular urlencoded data. Note that there are other ways to accomplish this. You can use ASP.NET MVC and a custom route, an HTTP Handler or separate ASPX page, or even a WCF REST service that’s configured to use non-JSON inputs. However if you want to use an ASP.NET AJAX service (or Page Methods) with a little bit of setup work it’s actually quite easy to capture all the form variables on the client and ship them up to the server. The basic steps needed to make this happen are: Capture form variables into an array on the client with jQuery’s .serializeArray() function Use $.ajax() or my ServiceProxy class to make an AJAX call to the server to send this array On the server create a custom type that matches the .serializeArray() name/value structure Create extension methods on NameValue[] to easily extract form variables Create a [WebMethod] that accepts this name/value type as an array (NameValue[]) This seems like a lot of work but realize that steps 3 and 4 are a one time setup step that can be reused in your entire site or multiple applications. Let’s look at a short example that looks like this as a base form of fields to ship to the server: The HTML for this form looks something like this: <div id="divMessage" class="errordisplay" style="display: none"> </div> <div> <div class="label">Name:</div> <div><asp:TextBox runat="server" ID="txtName" /></div> </div> <div> <div class="label">Company:</div> <div><asp:TextBox runat="server" ID="txtCompany"/></div> </div> <div> <div class="label" ></div> <div> <asp:DropDownList runat="server" ID="lstAttending"> <asp:ListItem Text="Attending" Value="Attending"/> <asp:ListItem Text="Not Attending" Value="NotAttending" /> <asp:ListItem Text="Maybe Attending" Value="MaybeAttending" /> <asp:ListItem Text="Not Sure Yet" Value="NotSureYet" /> </asp:DropDownList> </div> </div> <div> <div class="label">Special Needs:<br /> <small>(check all that apply)</small></div> <div> <asp:ListBox runat="server" ID="lstSpecialNeeds" SelectionMode="Multiple"> <asp:ListItem Text="Vegitarian" Value="Vegitarian" /> <asp:ListItem Text="Vegan" Value="Vegan" /> <asp:ListItem Text="Kosher" Value="Kosher" /> <asp:ListItem Text="Special Access" Value="SpecialAccess" /> <asp:ListItem Text="No Binder" Value="NoBinder" /> </asp:ListBox> </div> </div> <div> <div class="label"></div> <div> <asp:CheckBox ID="chkAdditionalGuests" Text="Additional Guests" runat="server" /> </div> </div> <hr /> <input type="button" id="btnSubmit" value="Send Registration" /> The form includes a few different kinds of form fields including a multi-selection listbox to demonstrate retrieving multiple values. Setting up the Server Side [WebMethod] The [WebMethod] on the server we’re going to call is going to be very simple and just capture the content of these values and echo then back as a formatted HTML string. Obviously this is overly simplistic but it serves to demonstrate the simple point of capturing the POST data on the server in an AJAX callback. public class PageMethodsService : System.Web.Services.WebService { [WebMethod] public string SendRegistration(NameValue[] formVars) { StringBuilder sb = new StringBuilder(); sb.AppendFormat("Thank you {0}, <br/><br/>", HttpUtility.HtmlEncode(formVars.Form("txtName"))); sb.AppendLine("You've entered the following: <hr/>"); foreach (NameValue nv in formVars) { // strip out ASP.NET form vars like _ViewState/_EventValidation if (!nv.name.StartsWith("__")) { if (nv.name.StartsWith("txt") || nv.name.StartsWith("lst") || nv.name.StartsWith("chk")) sb.Append(nv.name.Substring(3)); else sb.Append(nv.name); sb.AppendLine(": " + HttpUtility.HtmlEncode(nv.value) + "<br/>"); } } sb.AppendLine("<hr/>"); string[] needs = formVars.FormMultiple("lstSpecialNeeds"); if (needs == null) sb.AppendLine("No Special Needs"); else { sb.AppendLine("Special Needs: <br/>"); foreach (string need in needs) { sb.AppendLine("&nbsp;&nbsp;" + need + "<br/>"); } } return sb.ToString(); } } The key feature of this method is that it receives a custom type called NameValue[] which is an array of NameValue objects that map the structure that the jQuery .serializeArray() function generates. There are two custom types involved in this: The actual NameValue type and a NameValueExtensions class that defines a couple of extension methods for the NameValue[] array type to allow for single (.Form()) and multiple (.FormMultiple()) value retrieval by name. The NameValue class is as simple as this and simply maps the structure of the array elements of .serializeArray(): public class NameValue { public string name { get; set; } public string value { get; set; } } The extension method class defines the .Form() and .FormMultiple() methods to allow easy retrieval of form variables from the returned array: /// <summary> /// Simple NameValue class that maps name and value /// properties that can be used with jQuery's /// $.serializeArray() function and JSON requests /// </summary> public static class NameValueExtensionMethods { /// <summary> /// Retrieves a single form variable from the list of /// form variables stored /// </summary> /// <param name="formVars"></param> /// <param name="name">formvar to retrieve</param> /// <returns>value or string.Empty if not found</returns> public static string Form(this NameValue[] formVars, string name) { var matches = formVars.Where(nv => nv.name.ToLower() == name.ToLower()).FirstOrDefault(); if (matches != null) return matches.value; return string.Empty; } /// <summary> /// Retrieves multiple selection form variables from the list of /// form variables stored. /// </summary> /// <param name="formVars"></param> /// <param name="name">The name of the form var to retrieve</param> /// <returns>values as string[] or null if no match is found</returns> public static string[] FormMultiple(this NameValue[] formVars, string name) { var matches = formVars.Where(nv => nv.name.ToLower() == name.ToLower()).Select(nv => nv.value).ToArray(); if (matches.Length == 0) return null; return matches; } } Using these extension methods it’s easy to retrieve individual values from the array: string name = formVars.Form("txtName"); or multiple values: string[] needs = formVars.FormMultiple("lstSpecialNeeds"); if (needs != null) { // do something with matches } Using these functions in the SendRegistration method it’s easy to retrieve a few form variables directly (txtName and the multiple selections of lstSpecialNeeds) or to iterate over the whole list of values. Of course this is an overly simple example – in typical app you’d probably want to validate the input data and save it to the database and then return some sort of confirmation or possibly an updated data list back to the client. Since this is a full AJAX service callback realize that you don’t have to return simple string values – you can return any of the supported result types (which are most serializable types) including complex hierarchical objects and arrays that make sense to your client code. POSTing Form Variables from the Client to the AJAX Service To call the AJAX service method on the client is straight forward and requires only use of little native jQuery plus JSON serialization functionality. To start add jQuery and the json2.js library to your page: <script src="Scripts/jquery.min.js" type="text/javascript"></script> <script src="Scripts/json2.js" type="text/javascript"></script> json2.js can be found here (be sure to remove the first line from the file): http://www.json.org/json2.js It’s required to handle JSON serialization for those browsers that don’t support it natively. With those script references in the document let’s hookup the button click handler and call the service: $(document).ready(function () { $("#btnSubmit").click(sendRegistration); }); function sendRegistration() { var arForm = $("#form1").serializeArray(); $.ajax({ url: "PageMethodsService.asmx/SendRegistration", type: "POST", contentType: "application/json", data: JSON.stringify({ formVars: arForm }), dataType: "json", success: function (result) { var jEl = $("#divMessage"); jEl.html(result.d).fadeIn(1000); setTimeout(function () { jEl.fadeOut(1000) }, 5000); }, error: function (xhr, status) { alert("An error occurred: " + status); } }); } The key feature in this code is the $("#form1").serializeArray();  call which serializes all the form fields of form1 into an array. Each form var is represented as an object with a name/value property. This array is then serialized into JSON with: JSON.stringify({ formVars: arForm }) The format for the parameter list in AJAX service calls is an object with one property for each parameter of the method. In this case its a single parameter called formVars and we’re assigning the array of form variables to it. The URL to call on the server is the name of the Service (or ASPX Page for Page Methods) plus the name of the method to call. On return the success callback receives the result from the AJAX callback which in this case is the formatted string which is simply assigned to an element in the form and displayed. Remember the result type is whatever the method returns – it doesn’t have to be a string. Note that ASP.NET AJAX and WCF REST return JSON data as a wrapped object so the result has a ‘d’ property that holds the actual response: jEl.html(result.d).fadeIn(1000); Slightly simpler: Using ServiceProxy.js If you want things slightly cleaner you can use the ServiceProxy.js class I’ve mentioned here before. The ServiceProxy class handles a few things for calling ASP.NET and WCF services more cleanly: Automatic JSON encoding Automatic fix up of ‘d’ wrapper property Automatic Date conversion on the client Simplified error handling Reusable and abstracted To add the service proxy add: <script src="Scripts/ServiceProxy.js" type="text/javascript"></script> and then change the code to this slightly simpler version: <script type="text/javascript"> proxy = new ServiceProxy("PageMethodsService.asmx/"); $(document).ready(function () { $("#btnSubmit").click(sendRegistration); }); function sendRegistration() { var arForm = $("#form1").serializeArray(); proxy.invoke("SendRegistration", { formVars: arForm }, function (result) { var jEl = $("#divMessage"); jEl.html(result).fadeIn(1000); setTimeout(function () { jEl.fadeOut(1000) }, 5000); }, function (error) { alert(error.message); } ); } The code is not very different but it makes the call as simple as specifying the method to call, the parameters to pass and the actions to take on success and error. No more remembering which content type and data types to use and manually serializing to JSON. This code also removes the “d” property processing in the response and provides more consistent error handling in that the call always returns an error object regardless of a server error or a communication error unlike the native $.ajax() call. Either approach works and both are pretty easy. The ServiceProxy really pays off if you use lots of service calls and especially if you need to deal with date values returned from the server  on the client. Summary Making Web Service calls and getting POST data to the server is not always the best option – ASP.NET and WCF AJAX services are meant to work with data in objects. However, in some situations it’s simply easier to POST all the captured form data to the server instead of mapping all properties from the input fields to some sort of message object first. For this approach the above POST mechanism is useful as it puts the parsing of the data on the server and leaves the client code lean and mean. It’s even easy to build a custom model binder on the server that can map the array values to properties on an object generically with some relatively simple Reflection code and without having to manually map form vars to properties and do string conversions. Keep in mind though that other approaches also abound. ASP.NET MVC makes it pretty easy to create custom routes to data and the built in model binder makes it very easy to deal with inbound form POST data in its original urlencoded format. The West Wind West Wind Web Toolkit also includes functionality for AJAX callbacks using plain POST values. All that’s needed is a Method parameter to query/form value to specify the method to be called on the server. After that the content type is completely optional and up to the consumer. It’d be nice if the ASP.NET AJAX Service and WCF AJAX Services weren’t so tightly bound to the content type so that you could more easily create open access service endpoints that can take advantage of urlencoded data that is everywhere in existing pages. It would make it much easier to create basic REST endpoints without complicated service configuration. Ah one can dream! In the meantime I hope this article has given you some ideas on how you can transfer POST data from the client to the server using JSON – it might be useful in other scenarios beyond ASP.NET AJAX services as well. Additional Resources ServiceProxy.js A small JavaScript library that wraps $.ajax() to call ASP.NET AJAX and WCF AJAX Services. Includes date parsing extensions to the JSON object, a global dataFilter for processing dates on all jQuery JSON requests, provides cleanup for the .NET wrapped message format and handles errors in a consistent fashion. Making jQuery Calls to WCF/ASMX with a ServiceProxy Client More information on calling ASMX and WCF AJAX services with jQuery and some more background on ServiceProxy.js. Note the implementation has slightly changed since the article was written. ww.jquery.js The West Wind West Wind Web Toolkit also includes ServiceProxy.js in the West Wind jQuery extension library. This version is slightly different and includes embedded json encoding/decoding based on json2.js.© Rick Strahl, West Wind Technologies, 2005-2010Posted in jQuery  ASP.NET  AJAX  

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