Search Results

Search found 9889 results on 396 pages for 'behind the compiler'.

Page 112/396 | < Previous Page | 108 109 110 111 112 113 114 115 116 117 118 119  | Next Page >

  • C Run-Time library part 2

    - by b-gen-jack-o-neill
    Hi, I was suggested when I have some further questions on my older ones, to create newer Question and reffer to old one. So, this is the original question: What is the C runtime library? OK, from your answers, I now get thet statically linked libraries are Microsoft implementation of C standart functions. Now: If I get it right, the scheme would be as follow: I want to use printf(), so I must include which just tels compiler there us functio printf() with these parameters. Now, when I compile code, becouse printf() is defined in C Standart Library, and becouse Microsoft decided to name it C Run Time library, it gets automatically statically linked from libcmt.lib (if libcmt.lib is set in compiler) at compile time. I ask, becouse on wikipedia, in article about runtime library there is that runtime library is linked in runtime, but .lib files are linked at compile time, am I right? Now, what confuses me. There is .dll version of C standart library. But I thought that to link .dll file, you must actually call winapi program to load that library. So, how can be these functions dynamically linked, if there is no static library to provide code to tell Windows to load desired functions from dll? And really last question on this subject - are C Standart library functions also calls to winapi even they are not .dll files like more advanced WinAPI functions? I mean, in the end to access framebuffer and print something you must tell Windows to do it, since OS cannot let you directly manipulate HW. I think of it like the OS must be written to support all C standart library functions same way across similiar versions, since they are statically linked, and can differently support more complex WinAPI calls becouse new version of OS can have adjustements in the .dll file.

    Read the article

  • How do I get a ComboBox SelectionChanged event to fire from a nested ListBoxItem?

    - by Stephen McCusker
    This is a rather complex problem that has me really confused right now. Any help would be greatly appreciated. The Setup: ListBox of Type A UserControls -ListBoxItem of Type A UserControl --ListBox of Type B UserControls ---ListBoxItem of Type B UserControl ----ListBox of Type C UserControls -----ListBoxItem of Type C UserControl (contains the ComboBox) In other words, the Type A control has a ListBox of Type B controls that has a ListBox of Type C controls. All of the controls are hierarchical in nature. Type A contains the data that's needed to load the Type B controls and the Type B contains the data that's needed to load the Type C controls. The Type C control has a standard ComboBox in it for changing the values of the present items. In addition to the above structure, I have drag and dropping tied to the PreviewMouseLeftButtonDown event on both the Type A and Type B UserControl levels to handle reordering/deleting/etc commands in the GUI. All of this is working as intended. The Problem: When I attempt to change the value in the ComboBox, the SelectionChanged event never fires on the Type C "level" unless I'm careful enough to click on the borders/spacing in between any Type A or B controls. This happens when my ComboBox popout menu overlaps on either a Type A or B control located below itself. The selection events for Type A or B are firing instead of the Type C events, so the ComboBox is never changing its value reliably. In the debugger, the code for handling the drag and drop is triggering on the next ListBoxItem that's located underneath the ComboBox. Thoughts: Is there a way I can make my ComboBox popup take prevalence over the items behind it while double-nested in a ListBox (ie, ignore anything behind it while it's open)? Is there some way to reroute the incorrectly firing SelectionChanged events down to the ComboBox that's supposed to be triggering them?

    Read the article

  • Using unset member variables within a class or struct

    - by Doug Kavendek
    It's pretty nice to catch some really obvious errors when using unset local variables or when accessing a class or struct's members directly prior to initializing them. In visual studio 2008 you get an "uninitialized local variable used" warning at compile-time and get a run-time check failure at the point of access when debugging. However, if you access an uninitialized struct's member variable through one of its functions, you don't get any warnings or assertions. Obviously the easiest solution is don't do that, but nobody's perfect. For example: struct Test { float GetMember() const { return member; } float member; }; Test test; float f1 = test.member; // Raises warning, asserts in VS debugger at runtime float f2 = test.GetMember(); // No problem, just keeps on going This surprised me, but it makes some sense -- the compiler can't assume calling a function on an unused struct is an error, or how else would you initialize or construct it? And anything fancier just quickly brings up so many other complications that it makes sense that it wouldn't bother classifying which functions are ok to call and when, especially just as a debugging help. I know I can set up my own assertions or error checking within the class itself, but that can complicate some simpler structs. Still, it would seem like within the context of the function call, wouldn't it know insides GetMember() that member wasn't initialized yet? I'm assuming it's not only relying on static compile-time deduction, given the Run-Time Check Failure #3 it raises during execution, so based on my current understanding of it it would seem reasonable for the same checks to apply. Is this just a limitation of this specific compiler/debugger (Visual Studio 2008), or more tied to how C++ works?

    Read the article

  • parse content away from structure in a binary file

    - by Jeff Godfrey
    Using C#, I need to read a packed binary file created using FORTRAN. The file is stored in an "Unformatted Sequential" format as described here (about half-way down the page in the "Unformatted Sequential Files" section): http://www.tacc.utexas.edu/services/userguides/intel8/fc/f_ug1/pggfmsp.htm As you can see from the URL, the file is organized into "chunks" of 130 bytes or less and includes 2 length bytes (inserted by the FORTRAN compiler) surrounding each chunk. So, I need to find an efficient way to parse the actual file payload away from the compiler-inserted formatting. Once I've extracted the actual payload from the file, I'll then need to parse it up into its varying data types. That'll be the next exercise. My first thoughts are to slurp up the entire file into a byte array using File.ReadAllBytes. Then, just iterate through the bytes, skipping the formatting and transferring the actual data to a second byte array. In the end, that second byte array should contain the actual file contents minus all the formatting, which I'd then need to go back through to get what I need. As I'm fairly new to C#, I thought there might be a better, more accepted way of tackling this. Also, in case it's helpful, these files could be fairly large (say 30MB), though most will be much smaller...

    Read the article

  • Understanding sql queries formulation methodoloy. How do you think while formulating Sql Queries

    - by Shantanu Gupta
    I have been working on sql server and front end coding and have usually faced problem formulating queries. I do understand most of the concepts of sql that are needed in formulating queries but whenever some new functionality comes into the picture that can be dont using sql query, i do usually fails resolving them. I am very comfortable with select queries using joins and all such things but when it comes to DML operation i usually fails For every query that i never done before I usually finds uncomfortable with that while creating them. Whenever I goes for an interview I usually faces this problem. Is it their some concept behind approaching on formulating sql queries. Eg. I need to create an sql query such that A table contain single column having duplicate record. I need to remove duplicate records. I know i can find the solution to this query very easily on Googling, but I want to know how everyone comes to the desired result. Is it something like Practice Makes Man Perfect i.e. once you did it, next time you will be able to formulate or their is some logic or concept behind.

    Read the article

  • How to get a Class literal from a generically specific Class

    - by h2g2java
    There are methods like these which require Class literals as argument. Collection<EmpInfo> emps = SomeSqlUtil.select( EmpInfo.class, "select * from emps"); or GWT.create(Razmataz.class); The problem presents itself when I need to supply generic specific classes like EmpInfo<String> Razmataz<Integer> The following would be wrong syntax Collection<EmpInfo<String>> emps = SomeSqlUtil.select( EmpInfo<String>.class, "select * from emps"); or GWT.create(Razmataz<Integer>.class); Because you cannot do syntax like Razmataz<Integer>.class So, how would I be able to squeeze a class literal out of EmpInfo<String> Razmataz<Integer> so that I could feed them as arguments to methods requiring Class literals? Further info Okay, I confess that I am asking this primarily for GWT. I have a pair of GWT RPC interface Razmataz. (FYI, GWT RPC interface has to be defined in server-client pairs). I plan to use the same interface pair for communicating whether it be String, Integer, Boolean, etc. GWT.create(Razmataz) for Razmataz<T> complains that, since I did not specify T, GWT compiler treated it as Object. Then GWT compiler would not accept Object class. It needs to be more specific than being an Object. So, it seems there is no way for me to tell GWT.create what T is because a Class literal is a runtime concept while generics is a compile time concept, Right?

    Read the article

  • Consecutive Tables in Latex

    - by Tim
    Hi, I wonder how to place several tables consecutively in Latex? The page with the text right before the first table has a little space but not enough for the first table, so the first table is to be placed on the top of the next page, although I use "\begin{table}[!h]" for it. The second table does not fit into the place in the rest of the page of the first table, so I think I might use longtable for it to span the rest of the page and the top of the next page. Similarly, I use longtable for the third table. The latex code is as follows: ... % some text \begin{table}[!h] \caption{Table 1. \label{tab:1}} \begin{center} \begin{tabular}{c c} ... \end{tabular} \end{center} \end{table} \begin{center} \begin{longtable}{ c c } \caption{Table 2. \label{tab:2}}\\ ... \end{longtable} \end{center} \begin{center} \begin{longtable}{ c c } \caption{Table 3. \label{tab:3}}\\ ... \end{longtable} \end{center} ... % some text In the compiled pdf file it turns out that the order of the tables is messed up. The first table is placed behind the second and third one, and the second one spans the page with text before the tables and the next page with the third one following it. I would like to know how I can make the three tables appear consecutively in order, and there are no space left blank between them and between the text and the tables? Or if what I hope is not possible, what is the best strategy then? Thanks and regards! EDIT: Removing [!h] does not make improvement, the first table is still behind the second and the third.

    Read the article

  • Template compiling errors on iPhone SDK 3.2

    - by Didier Malenfant
    I'm porting over some templated code from Windows and I'm hitting some compiler differences on the iPhone 3.2 SDK. Original code inside a class template's member function is: return BinarySearch<uint32, CSimpleKey<T> >(key); where BinarySearch is a method inherited from another template. This produces the following error: csimplekeytable.h:131: error: no matching function for call to 'BinarySearch(NEngine::uint32&)' The visual studio compiler seems to walk up the template hierarchy fine but gcc needs me to fully qualify where the function comes from (I have verified this by fixing the same issues with template member variables that way). So I now need to change this into: return CSimpleTable<CSimpleKey<T> >::BinarySearch<uint32, CSimpleKey<T> >(key); Which now produces the following error: csimplekeytable.h:132: error: expected primary-expression before ',' token csimplekeytable.h:132: error: expected primary-expression before '>' token After some head scratching, I believe what's going on here is that it's trying to resolve the '<' before BinarySearch as a 'Less Than' operator for some reason. So two questions: - Am I on the right path with my interpretation of the error? - How do I fix it? -D

    Read the article

  • Compile Assembly Output generated by VC++?

    - by SDD
    I have a simple hello world C program and compile it with /FA. As a consequence, the compiler also generates the corresponding assembly listing. Now I want to use masm/link to assemble an executable from the generated .asm listing. The following command line yields 3 linker errors: \masm32\bin\ml /I"C:\Program Files (x86)\Microsoft Visual Studio 9.0\VC\include" /c /coff asm_test.asm \masm32\bin\link /SUBSYSTEM:CONSOLE /LIBPATH:"C:\Program Files (x86)\Microsoft Visual Studio 9.0\VC\lib" asm_test.obj indicating that the C-runtime functions were not linked to the object files produced earlier: asm_test.obj : error LNK2001: unresolved external symbol @__security_check_cookie@4 asm_test.obj : error LNK2001: unresolved external symbol _printf LINK : error LNK2001: unresolved external symbol _wmainCRTStartup asm_test.exe : fatal error LNK1120: 3 unresolved externals Here is the generated assembly listing ; Listing generated by Microsoft (R) Optimizing Compiler Version 15.00.30729.01 TITLE c:\asm_test\asm_test\asm_test.cpp .686P .XMM include listing.inc .model flat INCLUDELIB OLDNAMES PUBLIC ??_C@_0O@OBPALAEI@hello?5world?$CB?6?$AA@ ; `string' EXTRN @__security_check_cookie@4:PROC EXTRN _printf:PROC ; COMDAT ??_C@_0O@OBPALAEI@hello?5world?$CB?6?$AA@ CONST SEGMENT ??_C@_0O@OBPALAEI@hello?5world?$CB?6?$AA@ DB 'hello world!', 0aH, 00H ; `string' CONST ENDS PUBLIC _wmain ; Function compile flags: /Ogtpy ; COMDAT _wmain _TEXT SEGMENT _argc$ = 8 ; size = 4 _argv$ = 12 ; size = 4 _wmain PROC ; COMDAT ; File c:\users\octon\desktop\asm_test\asm_test\asm_test.cpp ; Line 21 push OFFSET ??_C@_0O@OBPALAEI@hello?5world?$CB?6?$AA@ call _printf add esp, 4 ; Line 22 xor eax, eax ; Line 23 ret 0 _wmain ENDP _TEXT ENDS END I am using the latest masm32 version (6.14.8444).

    Read the article

  • Separating Content (aspx) from Code (aspx.cs) in ASP.NET

    - by firedrawndagger
    I would like to know what is the best practice on separating the content of an aspx page (ASP.NET 3.5) from the code (I'm using C#). I have a form that users can type data in - for example they are allowed to enter a percent. If they Otherwise for example I would like to display the following error messages: <p id="errormsg" class="percenthigh">Please enter a percent below 100</p> <p id="errormsg" class="percentnegative">Percent cannot be below 0</p> <p id="errormsg" class="percentnot">This is not a percent</p> So in essence I'm hiding the error messages and showing one depending on what the user input is. I believe this is the best way to seperate the content from the code behind. However, how do I select elements and hide/unhide them depending on the user input? I'm aware I can do a runat="server" on the elements but the problem is that I can't select by class and am limited only to ID's. What workarounds do you recommend? Aside from putting in the values in code behind which is notoriously difficult to debug. Also has this been "fixed" in ASP.NET 4?

    Read the article

  • ASP.NET catching controls from html generated from the database

    - by Drahcir
    I have a set of websites that basically do the exact same thing in terms of functionality, the only thing that varies is the css and how the html is laid out. Is there a way to generate the html from a database (ie retreiving the html from a table) and then catching the controls (like buttons, textboxes etc) from the code behind? UPDATE: Here is an example of what I want to acheive: <html> <div id="generatedContent" runat="server"> <!-- the following content has been generated from the database on the page load event --> <div> This is a textbox <input id="tb1" runat="server" type="text" /> This is a button <input type="submit" id="btn1" runat="server" value="My Button" /> </div> </div> </html> This is the code behind var tb1 = new HtmlControls.HtmlInputText(); tb1 = FindControl("tb1"); var btn1 = new New HtmlControls.HtmlInputSubmit(); btn1 = FindControl("btn1"); Now obviously since the html has been generated from the database (ie after the page has already been initialised) the FindControl method will return null.

    Read the article

  • Why compiling in Flash IDE I cannot access stage in a Sprite constructor before addChild while if I

    - by yuri
    I've created this simple class (omissing package directive and imports) public class Viewer extends Sprite { public function Viewer():void { trace(stage); } } then in Flash IDE I import in first frame this AS: import Viewer var viewer = new Viewer(); stage.addChild(viewer); trace(viewer.stage); and this works as I expected: the first trace called in constructor say stage is "null" because I haven't yet add viewer to a DisplayObjectContainer. The second one output the stage object. So I created a project using AXDT eclipse plugin, I've recreated and compiled only the first class (trashed the AS init script used in Flash IDE because is not needed) and on the first trace ... wow ... the stage is filled with the stage Object. I seems to me that the compiler used by AXDT (Flex4 SDK open source) add the class... before construct it (!?).. to a DisplayObjectContainer already attached to a Stage. I want to understand how can reproduce this behaviour using compiler in Flash IDE so I can directrly access Stage in construction.

    Read the article

  • Compiling scipy on Windows 32-bit

    - by Sridhar Ratnakumar
    Has anyone tried compiling SciPy on Windows using numpy-1.3.0 that was built with the pre-built ATLAS libraries (atlas3.6.0_WinNT_P4SSE2.zip) linked in the installation document. I get the following linker error, and have no ideas as to how to fix this issue. $ python setup.py config --compiler=mingw32 build --compiler=mingw32 install --root=i [...] creating build\temp.win32-2.6\Release creating build\temp.win32-2.6\Release\scipy creating build\temp.win32-2.6\Release\scipy\integrate compile options: '-DNO_ATLAS_INFO=2 -I"C:\Documents and Settings\apy\Application Data\Python\Python26\site-packages\numpy\core\inc lude" -IC:\Python26\include -IC:\Python26\PC -c' gcc -mno-cygwin -O2 -Wall -Wstrict-prototypes -DNO_ATLAS_INFO=2 -I"C:\Documents and Settings\apy\Application Data\Python\Python26\ site-packages\numpy\core\include" -IC:\Python26\include -IC:\Python26\PC -c scipy\integrate\_odepackmo dule.c -o build\temp.win32-2.6\Release\scipy\integrate\_odepackmodule.o C:\MinGW\bin\g77.exe -g -Wall -mno-cygwin -g -Wall -mno-cygwin -shared build\temp.win32-2.6\Release\scipy\integrate\_odepackmodule .o -LC:\atlas3.6.0_WinNT_P4SSE2 -LC:\MinGW\lib -LC:\MinGW\lib\gcc\mingw32\3.4.5 -LC:\Python26\libs -LC:\Act ivePython32Python26\PCbuild -Lbuild\temp.win32-2.6 -lodepack -llinpack_lite -lmach -latlas -lcblas -lf77blas -llapack -lpython26 - lg2c -o build\lib.win32-2.6\scipy\integrate\_odepack.pyd C:\atlas3.6.0_WinNT_P4SSE2/libf77blas.a(ATL_F77wrap_daxpy.o):ATL_F77wrap_axpy.c:(.text+0x3c): undefined reference to `ATL _daxpy' C:\atlas3.6.0_WinNT_P4SSE2/libf77blas.a(ATL_F77wrap_dscal.o):ATL_F77wrap_scal.c:(.text+0x26): undefined reference to `ATL _dscal' C:\atlas3.6.0_WinNT_P4SSE2/libf77blas.a(ATL_F77wrap_dcopy.o):ATL_F77wrap_copy.c:(.text+0x3d): undefined reference to `ATL _dcopy' C:\atlas3.6.0_WinNT_P4SSE2/libf77blas.a(ATL_F77wrap_idamax.o):ATL_F77wrap_amax.c:(.text+0x1e): undefined reference to `AT L_idamax' C:\atlas3.6.0_WinNT_P4SSE2/libf77blas.a(ATL_F77wrap_ddot.o):ATL_F77wrap_dot.c:(.text+0x36): undefined reference to `ATL_d dot' collect2: ld returned 1 exit status error: Command "C:\MinGW\bin\g77.exe -g -Wall -mno-cygwin -g -Wall -mno-cygwin -shared build\temp.win32-2.6\Release\scipy\integrat e\_odepackmodule.o -LC:\atlas3.6.0_WinNT_P4SSE2 -LC:\MinGW\lib -LC:\MinGW\lib\gcc\mingw32\3.4.5 -LC:\Python 26\libs -LC:\Python26\PCbuild -Lbuild\temp.win32-2.6 -lodepack -llinpack_lite -lmach -latlas -lcblas -lf77blas -llap ack -lpython26 -lg2c -o build\lib.win32-2.6\scipy\integrate\_odepack.pyd" failed with exit status 1 Does anyone know what could have gone wrong here?

    Read the article

  • Why do not C++11's move constructor/assignment operator act as expected

    - by xmllmx
    #include <iostream> using namespace std; struct A { A() { cout << "A()" << endl; } ~A() { cout << "~A()" << endl; } A(A&&) { cout << "A(A&&)" << endl; } A& operator =(A&&) { cout << "A& operator =(A&&)" << endl; return *this; } }; struct B { // According to the C++11, the move ctor/assignment operator // should be implicitly declared and defined. The move ctor // /assignment operator should implicitly call class A's move // ctor/assignment operator to move member a. A a; }; B f() { B b; // The compiler knows b is a temporary object, so implicitly // defined move ctor/assignment operator of class B should be // called here. Which will cause A's move ctor is called. return b; } int main() { f(); return 0; } My expected output should be: A() A(A&&) ~A() ~A() However, the actual output is: (The C++ compiler is: Visual Studio 2012) A() ~A() ~A() Is this a bug of VC++? or just my misunderstanding?

    Read the article

  • what are all the Optimize tricks that you know for asp.net code ?

    - by Aristos
    After some time of many code programming on asp.net, I discover the very big speed different between string and StringBuilder. I know that is very common and known but I just mention it for start. The second think that I have found to speed up the code, is to use the const, and not the static, for declare my configuration constants value (especial the strings). With the const, the compiler not create new object, but just place the value, on the point that you have ask it, but with the static declaration, is create a new memory object and keep its on the memory. My third trick, is when I search for string, I use hash values, and not the string itself. For example, if I need a List<string SomeValues, and place inside strings that I need to search them, I prefer to use List<int SomeHashValue, and I use the hash value to locate the strings. My forth thought that I was wandering, is if is better to place big strings in one line, or separate them in different lines with the + symbol to be more easy to read out. I make some tests and see that the compiler make a good job is some split the string, in many lines, using the + symbol. What other tricks/tips do you know and use on your programming to make it run faster, and maybe use less memory. Well I know, that some times, to make something run faster, you need more memory, more cache. My priority is on speed. Because Speed Counts.

    Read the article

  • Problems initializing a final variable in Java

    - by froadie
    I keep running into slight variations of a problem in Java and it's starting to get to me, and I can't really think of a proper way to get around it. I have an object property that is final, but dynamic. That is, I want the value to be constant once assigned, but the value can be different each runtime. So I declare the class level variable at the beginning of the class - say private final FILE_NAME;. Then, in the constructor, I assign it a value - say FILE_NAME = buildFileName(); The problem begins when I have code in the buildFileName() method that throws an exception. So I try something like this in the constructor: try{ FILE_NAME = buildFileName(); } catch(Exception e){ ... System.exit(1); } Now I have an error - "The blank final field FILE_NAME may not have been initialized." This is where I start to get slightly annoyed at Java's strict compiler. I know that this won't be a problem because if it gets to the catch the program will exit... But the compiler doesn't know that and so doesn't allow this code. If I try to add a dummy assignment to the catch, I get - "The final field FILE_NAME may already have been assigned." I clearly can't assign a default value before the try-catch because I can only assign to it once. Any ideas...?

    Read the article

  • Are programming languages and methods inefficient? (assembler and C knowledge needed)

    - by b-gen-jack-o-neill
    Hi, for a long time, I am thinking and studying output of C language compiler in assembler form, as well as CPU architecture. I know this may be silly to you, but it seems to me that something is very ineffective. Please, don´t be angry if I am wrong, and there is some reason I do not see for all these principles. I will be very glad if you tell me why is it designed this way. I actually truly believe I am wrong, I know the genius minds of people which get PCs together knew a reason to do so. What exactly, do you ask? I´ll tell you right away, I use C as a example: 1: Stack local scope memory allocation: So, typical local memory allocation uses stack. Just copy esp to ebp and than allocate all the memory via ebp. OK, I would understand this if you explicitly need allocate RAM by default stack values, but if I do understand it correctly, modern OS use paging as a translation layer between application and physical RAM, when address you desire is further translated before reaching actual RAM byte. So why don´t just say 0x00000000 is int a,0x00000004 is int b and so? And access them just by mov 0x00000000,#10? Because you wont actually access memory blocks 0x00000000 and 0x00000004 but those your OS set the paging tables to. Actually, since memory allocation by ebp and esp use indirect addressing, "my" way would be even faster. 2: Variable allocation duplicity: When you run application, Loader load its code into RAM. When you create variable, or string, compiler generates code that pushes these values on the top o stack when created in main. So there is actual instruction for do so, and that actual number in memory. So, there are 2 entries of the same value in RAM. One in form of instruction, second in form of actual bytes in the RAM. But why? Why not to just when declaring variable count at which memory block it would be, than when used, just insert this memory location?

    Read the article

  • Why does Microsoft advise against readonly fields with mutable values?

    - by Weeble
    In the Design Guidelines for Developing Class Libraries, Microsoft say: Do not assign instances of mutable types to read-only fields. The objects created using a mutable type can be modified after they are created. For example, arrays and most collections are mutable types while Int32, Uri, and String are immutable types. For fields that hold a mutable reference type, the read-only modifier prevents the field value from being overwritten but does not protect the mutable type from modification. This simply restates the behaviour of readonly without explaining why it's bad to use readonly. The implication appears to be that many people do not understand what "readonly" does and will wrongly expect readonly fields to be deeply immutable. In effect it advises using "readonly" as code documentation indicating deep immutability - despite the fact that the compiler has no way to enforce this - and disallows its use for its normal function: to ensure that the value of the field doesn't change after the object has been constructed. I feel uneasy with this recommendation to use "readonly" to indicate something other than its normal meaning understood by the compiler. I feel that it encourages people to misunderstand the meaning of "readonly", and furthermore to expect it to mean something that the author of the code might not intend. I feel that it precludes using it in places it could be useful - e.g. to show that some relationship between two mutable objects remains unchanged for the lifetime of one of those objects. The notion of assuming that readers do not understand the meaning of "readonly" also appears to be in contradiction to other advice from Microsoft, such as FxCop's "Do not initialize unnecessarily" rule, which assumes readers of your code to be experts in the language and should know that (for example) bool fields are automatically initialised to false, and stops you from providing the redundancy that shows "yes, this has been consciously set to false; I didn't just forget to initialize it". So, first and foremost, why do Microsoft advise against use of readonly for references to mutable types? I'd also be interested to know: Do you follow this Design Guideline in all your code? What do you expect when you see "readonly" in a piece of code you didn't write?

    Read the article

  • How do you send in the LayoutRoot into a RelayCommand via a EventToCommand?

    - by user298145
    Grid example with the trigger: <Grid x:Name="LayoutRoot" DataContext="{Binding ProjectGrid, Source={StaticResource Locator}}"> <i:Interaction.Triggers> <i:EventTrigger EventName="Loaded"> <GalaSoft_MvvmLight_Command:EventToCommand Command="{Binding LoadedCommand, Mode=OneWay}" PassEventArgsToCommand="True"/> </i:EventTrigger> </i:Interaction.Triggers> In my ViewModel I set the LoadedCommand like this: public RelayCommand<RoutedEventArgs> LoadedCommand {get;private set;} And in the ViewModel initializer I have this: public ProjectGridViewModel() { LoadedCommand = new RelayCommand<RoutedEventArgs>(e => { this.DoLoaded(e); } ); } Then, in my DoLoaded I'm trying to do this: Grid _projectGrid = null; public void DoLoaded(RoutedEventArgs e) { _projectGrid = e.OriginalSource as Grid; } You can see I'm trying to get rid of my Loaded="" in my Grid in my view, and do a RelayCommand instead. The issue is the OriginalSource brings back nothing. My loaded event is running nice this way, but I need to get the Grid in via the RoutedEventArgs it seems. I tried passing in the Grid in the EventCommand with CommandParameter="{Binding ElementName=LayoutRoot}", but this just crashes VS2010 when hitting F5 and running the project. Any ideas? Or a better way to do this? I had the Loaded event run in the views C# then call the ViewModel in the Views code-behind, but I'd like to do a nicer binding. Talking to the ViewMode in the Views code-behind feels like a hack.

    Read the article

  • ASP .NET confusion - server controls

    - by Brandi
    I have read through the information in this question: http://stackoverflow.com/questions/22084/asp-net-aspxxx-controls-versus-standard-html but am still rather confused. The situation was I was asked to do a web project where I made a wizard. When I was done with the project everyone asked why I had used an <asp:Wizard...>. I thought this was what was being asked for, but apparently not, so after this I was led to believe that server controls were just prototyping tools. However, the next project I did my DB queries through C# code-behind and loaded the results via html. I was then asked why I had not used a gridview and a dataset. Does anyone have a list of pros and cons why they would choose to use specific html controls over specific server controls and why? I guess I'm looking for a list... what server controls are okay to use and why? EDIT: I guess this question is open ended, so I'll clarify a few more specific questions... Is it okay to use very simple controls such as asp:Label or do these just end up wasting space? It seems like it would be difficult to access html in the code behind otherwise. Are there a few controls that should just never be used? Does anyone have a good resource that will show me pros and cons of each control?

    Read the article

  • How to use a VB usercontrol on a C# page?

    - by ks78
    Hopefully someone will be able to point me in the right direction. I've created a usercontrol in VB that handles paging more efficiently than the DataPager (at least for very large datasets). I'd like to use it in a C# project, but I've been having trouble getting it to work. I've tried simply adding PagingControl.ascx to the C# project, but when I do that the markup and VB code behind don't seem to see each other. --Is this a namespace issue? I've tried adding the PagingControl.ascx to its own VB project, then adding that project to the C# project's solution, as well as a reference. --That almost works. I can register the PagingControl usercontrol in the markup. I can access the usercontrol's properties in the code behind, but any property that involves the UI of the usercontrol fails. Its seems as if the usercontrol's form hasn't had a chance to load by the time the C# page's Page_Load event handler fires. --Maybe this is an "order of operations" problem? At what point in the C# page's lifetime should a usercontrol's form be loaded? If anyone has any ideas or insight, I'd really appreciate it. Thanks in advance.

    Read the article

  • Newbie question: When to use extern "C" { //code } ?

    - by Russel
    Hello, Maybe I'm not understanding the differences between C and C++, but when and why do we need to use: extern "C" { ? Apparently its a "linkage convention"? I read about it briefly and noticed that all the .h header files included with MSVS surround their code with it. What type of code exactly is "C code" and NOT "C++ code"? I thought C++ included all C code? I'm guessing that this is not the case and that C++ is different and that standard features/functions exist in one or the other but not both (ie: printf is C and cout is C++), but that C++ is backwards compatible though the extern "C" declaration. Is this correct? My next question depends on the answer to the first, but I'll ask it here anyway: Since MSVS header files that are written in C are surrounded by extern "C" { ... }, when would you ever need to use this yourself in your own code? If your code is C code and you are trying to compile it in a C++ compiler, shouldn't it work without problem because all the standard h files you include will already have the extern "C" thing in them with the C++ compiler? Do you have to use this when compiling in C++ but linking to alteady built C libraries or something? Please help clarify this for me... Thanks! --Keith

    Read the article

  • Cairo / GTK example code crashes when window is too big or maximized

    - by user1890673
    I have copied and compiled the source code available in the section titled "Full Source". http://cairographics.org/threaded_animation_with_cairo/ I adapted this code to a project that I'm working on only to find that the app would crash when I made the window too big. Going back to the original example code, it too crashes when the window is too big ( 1000x1000 or so). I narrowed down in the example that this line appears to be responsible: pixmap = gdk_pixmap_new(window-window,500,500,-1); Where pixmap is of type GdkPixmap*. Resizing the window overwrites pixmap with a new pixmap that is the size of the window. I am doing this in Eclipse Juno in Windows Vista, 32-bit. My compiler is MinGW version 0.5-beta-20120426-1. My GTK+ version is 2.24.10 and apparently Cairo is 1.10.2 I added all of the includes and libraries for GTK and also added compiler switch -mms-bitfields. Is there a limit to the size of a pixmap or something? I'm just starting with GTK with examples so I'm not sure where to go if this example doesn't work.

    Read the article

  • ASP.NET: ModalPopupExtender prevents button click event from firing

    - by C. Griffin
    Here is what I'm trying to do: Click a button on my page, which in turn makes (2) things happen: Display a ModalPopup to prevent the user from pressing any buttons or changing values Call my code behind method, hiding the ModalPopup when finished Here is the ASP markup: <asp:UpdatePanel ID="UpdatePanel2" runat="server" ChildrenAsTriggers="true" UpdateMode="Always"> <Triggers> <asp:AsyncPostBackTrigger ControlID="btnSaveData" EventName="Click" /> </Triggers> <ContentTemplate> <asp:Panel ID="pnlHidden" runat="server" style="display: none;"> <div> <h1>Saving...</h1> </div> </asp:Panel> <cc1:ModalPopupExtender ID="modalPopup" BackgroundCssClass="modalBackground" runat="server" TargetControlID="btnSaveData" PopupControlID="pnlHidden"> </cc1:ModalPopupExtender> <asp:Button ID="btnSaveData" runat="server" Text="Save Data" OnClick="btnSaveData_Click" /> </ContentTemplate> </asp:UpdatePanel> Now, here is my code behind C# code: protected void btnSaveData_Click(object sender, EventArgs e) { UpdateUserData(GetLoggedInUser()); modalPopup.Enabled = false; } Why doesn't this work? The ModalPopup displays perfectly, but the btnSaveData_Click event NEVER fires.

    Read the article

  • How to create an instance of object with RTTI in Delphi 2010?

    - by Paul
    As we all known, when we call a constructor of a class like this: instance := TSomeClass.Create; The Delphi compiler actually do the following things: Call the static NewInstance method to allocate memory and initialize the memory layout. Call the constructor method to perform the initialization of the class Call the AfterConstruction method It's simple and easy to understand. but I'm not very sure how the compiler handle exceptions in the second and the third step. It seems there are no explicit way to create an instance using a RTTI constructor method in D2010. so I wrote a simple function in the Spring Framework for Delphi to reproduce the process of the creation. class function TActivator.CreateInstance(instanceType: TRttiInstanceType; constructorMethod: TRttiMethod; const arguments: array of TValue): TObject; var classType: TClass; begin TArgument.CheckNotNull(instanceType, 'instanceType'); TArgument.CheckNotNull(constructorMethod, 'constructorMethod'); classType := instanceType.MetaclassType; Result := classType.NewInstance; try constructorMethod.Invoke(Result, arguments); except on Exception do begin if Result is TInterfacedObject then begin Dec(TInterfacedObjectHack(Result).FRefCount); end; Result.Free; raise; end; end; try Result.AfterConstruction; except on Exception do begin Result.Free; raise; end; end; end; I feel it maybe not 100% right. so please show me the way. Thanks!

    Read the article

< Previous Page | 108 109 110 111 112 113 114 115 116 117 118 119  | Next Page >