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  • how to change a while sql query loop into an array loop

    - by Mac Taylor
    hey guys i record number of queries of my website and in page the below script runs , 40 extra queries added to page . how can I change this sql connection into a propper and light one function tree_set($index) { //global $menu; Remove this. $q=mysql_query("select id,name,parent from cats where parent='$index'"); if(mysql_num_rows($q) === 0) { return; } // User $tree instead of the $menu global as this way there shouldn't be any data duplication $tree = $index > 0 ? '<ul>' : ''; // If we are on index 0 then we don't need the enclosing ul while($arr=mysql_fetch_assoc($q)) { $subFileCount=mysql_query("select id,name,parent from cats where parent='{$arr['id']}'"); if(mysql_num_rows($subFileCount) > 0) { $class = 'folder'; } else { $class = 'file'; } $tree .= '<li>'; $tree .= '<span class="'.$class.'">'.$arr['name'].'</span>'; $tree .=tree_set("".$arr['id'].""); $tree .= '</li>'."\n"; } $tree .= $index > 0 ? '</ul>' : ''; // If we are on index 0 then we don't need the enclosing ul return $tree; } i heard , this can be done by changing it into an array , but i don't know how to do so thanks in advance

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  • Calling a constructor to reinitialize variables doesn't seem to work?

    - by Matt
    I wanted to run 1,000 iterations of a program, so set a counter for 1000 in main. I needed to reinitialize various variables after each iteration, and since the class constructor had all the initializations already written out - I decided to call that after each iteration, with the result of each iteration being stored in a variable in main. However, when I called the constructor, it had no effect...it took me a while to figure out - but it didn't reinitialize anything! I created a function exactly like the constructor - so the object would have its own version. When I called that, it reinitialized everything as I expected. int main() { Class MyClass() int counter = 0; while ( counter < 1000 ) { stuff happens } Class(); // This is how I tried to call the constructor initially. // After doing some reading here, I tried: // Class::Class(); // - but that didn't work either /* Later I used... MyClass.function_like_my_constructor; // this worked perfectly */ } ...Could someone try to explain why what I did was wrong, or didn't work, or was silly or what have you? I mean - mentally, I just figured - crap, I can call this constructor and have all this stuff reinitialized. Are constructors (ideally) ONLY called when an object is created?

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  • for loop vs std::for_each with lambda

    - by Andrey
    Let's consider a template function written in C++11 which iterates over a container. Please exclude from consideration the range loop syntax because it is not yet supported by the compiler I'm working with. template <typename Container> void DoSomething(const Container& i_container) { // Option #1 for (auto it = std::begin(i_container); it != std::end(i_container); ++it) { // do something with *it } // Option #2 std::for_each(std::begin(i_container), std::end(i_container), [] (typename Container::const_reference element) { // do something with element }); } What are pros/cons of for loop vs std::for_each in terms of: a) performance? (I don't expect any difference) b) readability and maintainability? Here I see many disadvantages of for_each. It wouldn't accept a c-style array while the loop would. The declaration of the lambda formal parameter is so verbose, not possible to use auto there. It is not possible to break out of for_each. In pre- C++11 days arguments against for were a need of specifying the type for the iterator (doesn't hold any more) and an easy possibility of mistyping the loop condition (I've never done such mistake in 10 years). As a conclusion, my thoughts about for_each contradict the common opinion. What am I missing here?

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  • Why can't I overwrite the prototype of `Array` (`Array.prototype`)?

    - by user828896
    I set the prototype of Array as an instance of my, I think book.aa will display "aa", but it displays "undefined", why? Thanks! <html> <head> <title>Array Properties</title> <h2>Array Properties</h2> <script type="text/javascript"> function my() { this.aa = 'aa'; } Array.prototype = new my(); Array.prototype.bb = "bb"; var book = new Array(); book[0] = "War and Peace"; </script> </head> <body bgcolor="lightblue"> <script type="text/javascript"> document.write(book.aa+book.bb); </script> </body> </html>

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  • problem by displaying images stored in a MySQL database?

    - by user1400
    i have images in my blob field in database i use blow colde for displaying image but it does not show any pic , someone could tell me where is my wrong? this is my model: public function getListUser() { $select = $this->select() ->order('lastname DESC'); $adapter = new Zend_Paginator_Adapter_DbTableSelect ($select); return $adapter; } this my controller: $userModel = new Admin_Model_User(); $adapter = $userModel->getListUser(); $paginator = new Zend_Paginator ($adapter); $paginator->setItemCountPerPage(1); $page = $this->_request->getParam('page', 1); $paginator->setCurrentPageNumber($page); $this->view->paginator = $paginator; this my view code: <td style="width: 20%;"> <?php echo $this->lastname ?> </td> <td style="width: 20%;"><?php header("Content-type: image/gif"); print $this->image; ?></td>

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  • More efficient way of writing this javascript

    - by nblackburn
    I am creating a contact form for my website and and using javascript to the first layer of validation before submitting it which is then checked again via php but i am relatively new to javascript, here is my script... $("#send").click(function() { var fullname = $("input#fullname").val(); var email = $("input#email").val(); var subject = $("input#subject").val(); var message = $("textarea#message").val(); if (fullname == ""){ $("input#fullname").css("background","#d02624"); $("input#fullname").css("color","#121212"); }else{ $("input#fullname").css("background","#121212"); $("input#fullname").css("color","#5c5c5c"); } if (email == ""){ $("input#email").css("background","#d02624"); $("input#email").css("color","#121212"); }else{ $("input#email").css("background","#121212"); $("input#email").css("color","#5c5c5c"); } if (subject == ""){ $("input#subject").css("background","#d02624"); $("input#subject").css("color","#121212"); }else{ $("input#subject").css("background","#121212"); $("input#subject").css("color","#5c5c5c"); } if (message == ""){ $("textarea#message").css("background","#d02624"); $("textarea#message").css("color","#121212"); }else{ $("textarea#message").css("background","#121212"); $("textarea#message").css("color","#5c5c5c"); } if (name && email && subject && message != ""){ alert("YAY"); } }); How can i write this more efficiently and make the alert show if all the fields are filled out, thanks.

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  • Obj-c method override/polymorphism problem

    - by Rod
    Ok, so I'm using Objective-C. Now, say I have: TopClass : NSObject - (int) getVal {return 1;} MidClass : TopClass - (int) getVal {return 2;} BotClass : MidClass - (int) getVal {return 3;} I then put objects of each type into an NSMutableArray and take one out. What I want to do is run the getVal func on the appropriate object type, but when I put id a = [allObjects objectAtIndex:0]; if ([a isKindOfClass:[TopClass class]]) { int i; i = [a getVal]; } I get firstly a warning about multiple methods called getVal (presumably because the compiler can't determine the actual object type until runtime). But more seriously I also get an error "void value not ignored as it should be" and it won't compile. If I don't try and use the return from [a getVal] then it compiles fine e.g. [a getval]; //obviously no good if I want to use the return value It will also work if I use isMemberOfClass statements to cast the object to a class before running the function e.g. if ([a isMemberOfClass:[BotClass]) i = [(BotClass*) a getVal]; But surely I shouldn't have to do this to get the functionality I require? Otherwise I'll have to put in a statement for every single subclass, and worse have to add a new line if I add a new sub class, which rather defeats the point of method overriding doesn't it? Surely there is a better way?

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  • std::bind overload resolution

    - by bpw1621
    The following code works fine #include <functional> using namespace std; using namespace std::placeholders; class A { int operator()( int i, int j ) { return i - j; } }; A a; auto aBind = bind( &A::operator(), ref(a), _2, _1 ); This does not #include <functional> using namespace std; using namespace std::placeholders; class A { int operator()( int i, int j ) { return i - j; } int operator()( int i ) { return -i; } }; A a; auto aBind = bind( &A::operator(), ref(a), _2, _1 ); I have tried playing around with the syntax to try and explicitly resolve which function I want in the code that does not work without luck so far. How do I write the bind line in order to choose the call that takes the two integer arguments?

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  • Location of DB models in Zend Framework - want them centralized

    - by jeffkolez
    Maybe I've been staring at the problem too long and it's much simpler than I think, but I'm stuck right now. I have three websites that are going to share database models. I've structured my applications so that I have an application directory for each site and a public directory for each site. The DB models live in a directory in the library along with Zend Framework and my third party libraries. I use the Autoloader class and when I try to instantiate one of my DB classes, it fails. The library directory is in my include path, but for whatever reason it refuses to instantiate my classes. It will work if I have my models in my application directory, but that's not the point. They're supposed to be shared classes in a Library. $model = new Model_Login(); $model->hello_world(); This fails when its in the library. The class is just a test: class Model_Login { public function hello_world() { echo "hello world"; } } Everything works until I try to instantiate one of my models. I've even tried renaming the class to something else (Db_Login), but that doesn't work either. Any ideas? Thanks in advance.

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  • How to open multiple socket connections and do callbacks in PHP

    - by Click Upvote
    I'm writing some code which processes a queue of items. The way it works is this: Get the next item flagged as needing to be processed from the mysql database row. Request some info from a google API using Curl, wait until the info is returned. Do the remainder of the processing based on the info returned. Flag the item as processed in the db, move onto the next item. The problem is that on step # 2. Google sometimes takes 10-15 seconds to return the requested info, during this time my script has to remain halted and wait. I'm wondering if I could change the code to do the following instead: Get the next 5 items to be processed as usual. Request info for items 1-5 from google, one after the other. When the info for item 1 is returned, a 'callback' should be done which calls up a function or otherwise calls some code which then does the remainder of the processing on items 1-5. And then the script starts over until all pending items in db are marked processed. How can something like this be achieved?

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  • Checkbox not working properly for IE with jquery

    - by wildanjel
    Hi, I am trying using several asp.net checkboxes on a page, disabling them accordingly. <asp:CheckBox ID='chkMenuItem' runat='server' CssClass='HiddenText' Text='Test' onclick='<%#String.Format("checkChild({0});", Eval("id")) %>' /> on javascript, I am using the following code function checkChild(id) { for (i = 0; i < $("input[id*=hdnParentMenuItemID]").length; i++) { if ($('input[id*=hdnParentMenuItemID]')[i].value.split(':')[0] == id) { var childID = $('input[id*=hdnParentMenuItemID]')[i].value.split(':')[1]; if ($("#" + childID).attr("disabled")) //$("#" + childID).attr('disabled', ''); $("#" + childID).removeAttr("disabled"); else $("#" + childID).attr('disabled', true); } } } Now is the checkboxes are disabled once the page is loaded, the removeAttr section doesn't work. I tried to step through the debugger and the logic works perfectly fine. If the checkboxes aren't disabled on page load, the code works fine. I tried replacing disabled 'attributes' with 'checked' to see if the other attributes work fine and it works perfectly fine. I tried $("#" + childID).attr('disabled', ''); but it didnt work either. Note: It works perfect on FF and Chrome but doesnt work in IE. Thanks,

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  • How to detect if a RGB is fully transparent?

    - by omega
    In java, I want to make a fully transparent RGBA, and I do that by using public static int getTransparentRGB() { int r = 0; int g = 0; int b = 0; int a = 0; int new_pixel = (a << 24) | (r << 16) | (g << 8) | b; return new_pixel; } Color color = new Color(getTransparentRGB()); System.out.println(color.getAlpha()); // -> 255 ?! I purposely keep all rgba values 0. However after I create the Color object with the rgba value as the constructor, if I call .getAlpha(), I get 255 even though I made the rgb value with a 0 alpha. If it returns 255, how could I tell the difference between a Color object that wasn't transparent, because that would also have a 255 alpha. I expect the color object to return a 0 alpha based on the function above. Does anyone know whats going on? Thanks

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  • How do I set the dimensions of a custom component defined in an ActionScript class?

    - by user339681
    I'm trying to set the height of a vertical bar (activityBar) but it does not appear to do anything. i have tried something similar with the whole component, but setting the dimensions does nothing (even in the mxml used to instantiate the class). Indeed, I've added transparent graphics just to give the component some dimensions I'm not sure what I'm doing wrong. It's something bad though; my approach seems dire. FYI: I'm trying to create a mic activity bar that will respond to the mic by simply setting the height of the activityBar child (which seems to me to be more efficient than redrawing the graphics each time). Thanks for your help! package components { import mx.core.UIComponent; public class MicActivityBar extends UIComponent { public var activityBar:UIComponent; // Constructor public function MicActivityBar() { super(); this.opaqueBackground = 0xcc4444; graphics.beginFill(0xcccccc, 0); graphics.drawRect(0,-15,5,30); graphics.endFill();// background for bar activityBar = new UIComponent(); activityBar.graphics.beginFill(0xcccccc, 0.8); activityBar.graphics.drawRect(0,-15,5,20); activityBar.graphics.endFill(); activityBar.height=10; addChild(activityBar); } } }

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  • Filling array with numbers

    - by Ockonal
    Hello, I have such situation: There is 8 div-blocks with ids like 'rateN_wrapper' where is 'N' is the number of div: <div id="rate1_wrapper"> <a href="#" id="0_1">...</a> <a href="#" id="0_2">...</a> <a href="#" id="0_3">...</a> </div> <div id="rate2_wrapper"> <a href="#" id="1_1">...</a> <a href="#" id="1_2">...</a> <a href="#" id="1_3">...</a> </div> ... var ratings = new Array(); for (i=0; i < 8; i++) { ratings[i] = -1; // Default is unrated } for (i=0; i < 8; i++) { $('#rate' + i + '_wrapper a').click(function() { ratings[i] = parseInt( $(this).attr('id').split('_')[1] ); console.debug(ratings); }); } My work is to fill array in need place with clicked link's id (parsed). But it's always changes only latest element of array (8). Why?

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  • How to make smooth movements in OpenGL?

    - by thyrgle
    So this kind of on topic to my other OpenGL question (not my OpenGL ES question but OpenGL the desktop version). If you have someone press a key to move a square how do you make the square movement naturally and less jumpy but also at the same speed I have it now? This is my code for the glutKeyboardFunc() function: void handleKeypress(unsigned char key, int x, int y) { if (key == 'w') { for (int i = 0; i < 12; i++) { if (i == 1 || i == 7 || i == 10 || i == 4) { square[i] = square[i] + 1; } } glutPostRedisplay(); } if (key == 'd') { for (int i = 0; i < 12; i++) { if (i == 0 || i % 3 == 0) { square[i] = square[i] + 1; } } glutPostRedisplay(); } if (key == 's') { for (int i = 0; i < 12; i++) { if (i == 1 || i == 7 || i == 10 || i == 4) { square[i] = square[i] - 1; } } glutPostRedisplay(); } if (key == 'a') { for (int i = 0; i < 12; i++) { if (i == 0 || i % 3 == 0) { square[i] = square[i] - 1; } } glutPostRedisplay(); } } I'm sorry if this doesn't quite make sense I'll try to rephrase it in a better way if it doesn't make sense.

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  • “User Control” uses an incorrect event

    - by Lijo
    Hi, I am using two instances of a user control. But when I click on a button in the user control, both of the instances calls the function corresponding to the first event (AcknowledgeReceipt()) However, when I remove the first user control and clicks on the btnRequestClarification, it calls the correct method (RequestClarification()) Is there a way to correct this behavior? acknowledgeModificationPopupCtrl = (ConfirmationPopup)this.LoadControl("~/ConfirmationPopup.ascx"); plHConfirmationPopup.Controls.Add(acknowledgeModificationPopupCtrl); acknowledgeModificationPopupCtrl.ContinueClick += new EventHandler(AcknowledgeReceipt); RequiredFieldValidator reqFValidatorAcknowledge = (RequiredFieldValidator)acknowledgeModificationPopupCtrl.FindControl("reqValidatorTxt"); reqFValidatorAcknowledge.ValidationGroup = "AcknowledgeReceipt"; acknowledgeModificationPopupCtrl.ValidationGroup = "AcknowledgeReceipt"; btnAcknowledgeReceipt.Attributes.Add("onclick", "validateconfirmPopup('true','xx' ,’yyy','Note' ,'true'); return false;"); requestModificationPopupCtrl = (ConfirmationPopup)this.LoadControl("~/ConfirmationPopup.ascx"); plHConfirmationPopup.Controls.Add(requestModificationPopupCtrl); requestModificationPopupCtrl.ContinueClick += new EventHandler(RequestClarification); RequiredFieldValidator reqFValidator = (RequiredFieldValidator)requestModificationPopupCtrl.FindControl("reqValidatorTxt"); reqFValidator.ValidationGroup = "request"; requestModificationPopupCtrl.ValidationGroup = "request"; btnRequestClarification.Attributes.Add("onclick", "validateconfirmPopup('true',’kkk' ,’lll','ff' ,'true'); return false;"); Thanks Lijo

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  • Fast and efficient way to read a space separated file of numbers into an array?

    - by John_Sheares
    I need a fast and efficient method to read a space separated file with numbers into an array. The files are formatted this way: 4 6 1 2 3 4 5 6 2 5 4 3 21111 101 3 5 6234 1 2 3 4 2 33434 4 5 6 The first row is the dimension of the array [rows columns]. The lines following contain the array data. The data may also be formatted without any newlines like this: 4 6 1 2 3 4 5 6 2 5 4 3 21111 101 3 5 6234 1 2 3 4 2 33434 4 5 6 I can read the first line and initialize an array with the row and column values. Then I need to fill the array with the data values. My first idea was to read the file line by line and use the split function. But the second format listed gives me pause, because the entire array data would be loaded into memory all at once. Some of these files are in the 100 of MBs. The second method would be to read the file in chunks and then parse them piece by piece. Maybe somebody else has a better a way of doing this?

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  • How to store arbitrary data for some HTML tags

    - by nickf
    I'm making a page which has some interaction provided by javascript. Just as an example: links which send an AJAX request to get the content of articles and then display that data in a div. Obviously in this example, I need each link to store an extra bit of information: the id of the article. The way I've been handling it in case was to put that information in the href link this: <a class="article" href="#5"> I then use jQuery to find the a.article elements and attach the appropriate event handler. (don't get too hung up on the usability or semantics here, it's just an example) Anyway, this method works, but it smells a bit, and isn't extensible at all (what happens if the click function has more than one parameter? what if some of those parameters are optional?) The immediately obvious answer was to use attributes on the element. I mean, that's what they're for, right? (Kind of). <a articleid="5" href="link/for/non-js-users.html"> In my recent question I asked if this method was valid, and it turns out that short of defining my own DTD (I don't), then no, it's not valid or reliable. A common response was to put the data into the class attribute (though that might have been because of my poorly-chosen example), but to me, this smells even more. Yes it's technically valid, but it's not a great solution. Another method I'd used in the past was to actually generate some JS and insert it into the page in a <script> tag, creating a struct which would associate with the object. var myData = { link0 : { articleId : 5, target : '#showMessage' // etc... }, link1 : { articleId : 13 } }; <a href="..." id="link0"> But this can be a real pain in butt to maintain and is generally just very messy. So, to get to the question, how do you store arbitrary pieces of information for HTML tags?

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  • JQuery Cross-slide

    - by Foxticity
    I'm trying to cycle through 3 images with JQuery Cross-slide, but the images doesn't want to display, here is the basic code below. All 3 images are in 650 - 100 size, and they are in the correct location, but the images just don't want to display. What am i doing wrong?? <html> <body> <script src="jquery.js" type="text/javascript"></script> <script src="jquery.cross-slide.js" type="text/javascript"></script> <div id="crossslide" style="width:650px; height:100px;"></div> <script type="text/javascript"> //<!-- $(function(){ $("#crossslide").crossSlide({ speed: 45, fade: 1 }, [ { src: "01.jpg", dir:"up"}, { src: "02.jpg", dir:"down"}, { src: "03.jpg", dir:"left"} ]); }); // --> </script> </body> </html>

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  • linked list printing using while loop and combining like terms

    - by C Z
    i have a problem printing out my linked list. My program asks the user to enter many different coefficients and degrees and makes it a polynomial and using mergesort it sorts it and then prints it, now i want to combine like terms and i have a problem doing so. thats part of my function that i don't know what is wrong with it: Term* p; p=poly; if (p==0) cout<<"---empty list---"; while(p !=0) if (p->coef==(p->next)->coef){ cout<<(p->deg)+((p->next)->deg)<<"x^"<<(p->coef)<<endl; p=p->next;} if (p->coef !=(p->next)->coef){ cout<<p->deg<<"x"<<p->coef<<"+"; p=p->next;} cout<<endl; } and thats my struct: struct Term { int deg; float coef; Term *next; }; typedef Term* Poly;

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  • Help with string equality in Java

    - by annayena
    The following function accepts 2 strings, the 2nd (not 1st) possibly containing *'s (asterisks). An * is a replacement for a string (empty, 1 char or more), it can appear appear (only in s2) once, twice, more or not at all, it cannot be adjacent to another * (ab**c), no need to check that. public static boolean samePattern(String s1, String s2) It returns true if strings are of the same pattern. It must be recursive, not use any loops, static or global variables. Also it's prohibited to use the method equals in the String class. Can use local variables and method overloading. Can use only these methods: charAt(i), substring(i), substring(i, j), length(). Examples: 1: TheExamIsEasy; 2: "The*xamIs*y" ---> true 1: TheExamIsEasy; 2: "Th*mIsEasy*" ---> true 1: TheExamIsEasy; 2: "*" ---> true 1: TheExamIsEasy; 2: "TheExamIsEasy" ---> true 1: TheExamIsEasy; 2: "The*IsHard" ---> FALSE I am stucked on this question for many hours now! I need the solution in Java please kindly help me.

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  • How to determine if a C++ usertype has been registered with tolua

    - by czuger
    We use tolua++ to generate Lua bindings for C++ classes. Assume I have a C++ class: class Foo { //Some methods in Foo, irrelevant to question. }; and a tolua .pkg file with the following contents class Foo { }; Consider the following function: void call_some_lua_function(lua_State* luaState) { Foo* myFoo = new Foo(); tolua_pushusertype(luaState, (void*)myFoo, "Foo"); //More code to actually call Lua, irrelevant to question. } Now, the actual question: tolua_pushusertype causes a segfault in Lua if the 3rd parameter does not correspond to a valid fully qualified string of a C++ class that was registered with a call to tolua_cclass. So, if parameter 3 where "Bar", we get a segfault. What I would like to do is the following: void call_some_lua_function(lua_State* luaState) { //determine if tolua is aware of my type, how to do this? //Something like: //if(!tolua_iscpptype_registered("Foo")) //{ // abort gracefully //} Foo* myFoo = new Foo(); tolua_pushusertype(luaState, (void*)myFoo, "Foo"); //More code to actually call Lua, irrelevant to question. } Is there a way to do this using tolua?

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  • 2 basic but interesting questions about .NET

    - by b-gen-jack-o-neill
    Hi, when I first saw C#, I thought this must be some joke. I was starting with programming in C. But in C# you could just drag and drop objects, and just write event code to them. It was so simple. Now, I still like C the most, becouse I am very attracted to the basic low level operations, and C is just next level of assembler, with few basic routines, so I like it very much. Even more becouse I write little apps for microcontrollers. But yeasterday I wrote very simple control program for my microcontroller based LED cube in asm, and I needed some way to simply create animation sequences to the Cube. So, I remembered C#. I have practically NO C# skills, but still I created simple program to make animation sequences in about hour with GUI, just with help of google and help of the embeded function descriptions in C#. So, to get to the point, is there some other reason then top speed, to use any other language than C#? I mean, it is so effective. I know that Java is a bit of similiar, but I expect C# to be more Windows effective since its directly from Microsoft. The second question is, what is the advantage of compiling into CIL, and than run by CLR, than directly compile it into machine code? I know that portability is one, but since C# is mainly for Windows, wouldn´t it be more powerfull to just compile it directly? Thanks.

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  • error: 'void Base::output()' is protected within this context

    - by Bill
    I'm confused about the errors generated by the following code. In Derived::doStuff, I can access Base::output directly by calling it. Why can't I create a pointer to output() in the same context that I can call output()? (I thought protected / private governed whether you could use a name in a specific context, but apparently that is incomplete?) Is my fix of writing callback(this, &Derived::output); instead of callback(this, Base::output) the correct solution? #include <iostream> using std::cout; using std::endl; template <typename T, typename U> void callback(T obj, U func) { ((obj)->*(func))(); } class Base { protected: void output() { cout << "Base::output" << endl; } }; class Derived : public Base { public: void doStuff() { // call it directly: output(); Base::output(); // create a pointer to it: // void (Base::*basePointer)() = &Base::output; // error: 'void Base::output()' is protected within this context void (Derived::*derivedPointer)() = &Derived::output; // call a function passing the pointer: // callback(this, &Base::output); // error: 'void Base::output()' is protected within this context callback(this, &Derived::output); } }; int main() { Derived d; d.doStuff(); }

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  • const object in c++

    - by Codenotguru
    I have a question on constant objects. In the following program: class const_check{ int a; public: const_check(int i); void print() const; void print2(); }; const_check::const_check(int i):a(i) {} void const_check::print() const { int a=19; cout<<"The value in a is:"<<a; } void const_check::print2() { int a=10; cout<<"The value in a is:"<<a; } int main(){ const_check b(5); const const_check c(6); b.print2(); c.print(); } void print() is constant member function of the class const_check, so according to the definition of constants if any attempt to change int a it should result in an error but the program works fine for me.I think i am having some confusion here, can anybody tell me why the compiler is not flagging it as an error??

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