|
i'm a new programmer in VC++.
recently,i was troubled when establishing a new CTreeView class in my project.everytime i establish a new Class based on CTreeView,an error display:error C2504: 'CTreeView' : base class undefined.
meanwhile,when selectting the CTreeView,a corresponding infomation shows from automation:
the base class does not support automation.
since this,a correponding error C2504 show,what can i do?
|
|
|
|
|
#include "afxcview.h"
http://blog.joycode.com/jiangsheng
http://blog.csdn.net/jiangsheng
Command what is yours
Conquer what is not
---Kane
|
|
|
|
|
Hi,
i wanna read text file .
my text file contain double value ! i wanna read this
double value & copy them in array of double in MC++ .
But i can not understand.
is anyone help me?
Best Regards.
|
|
|
|
|
Proper C++ will do this for you, iostreams allow you to specify what you expect to read. I'm not sure if the System.IO namespace does this, or if you need to parse the string yourself.
Christian Graus - Microsoft MVP - C++
|
|
|
|
|
Hi,
Thanks a lot.
I use StreamReader and then readLine() then parse string !
But i found i can open file in binary ,then select which
type i wanna read.
Best Regards.
Mostafa
|
|
|
|
|
I have written an application using MFC CSocket.
I have done some test.
It seems that OnReceive processing waits the end of the OnIdle method. OnReceive don't interrupt OnIdle!!
Is it true ?
Thanks.
Emanuele Reverberi.
|
|
|
|
|
I was wondering how large applications are put together when you have various people working on them. I would imagine that each person would have classes that they are incharge of creating and then making them a dll file.
I am working on an application that has several parts. I created each part as its own project. I can not figure out how to combine them into one application.
For instance, I created an app that creates and formats some text. This is using the .net forms. The main application has a button that opens an instance of this text formating app. How can i get the text formatting app into my main program. I am not sure how to compile it as a dll because it always compiles into an exe. Any advise or resourses would be great. Thanks!
|
|
|
|
|
Anonymous wrote:
I am working on an application that has several parts. I created each part as its own project. I can not figure out how to combine them into one application.
They need to be dll's except for the display layer.
Anonymous wrote:
I was wondering how large applications are put together when you have various people working on them.
Source control, partial classes, discipline.
Anonymous wrote:
How can i get the text formatting app into my main program.
That's not how it works. You should create an application that contains all the UI for your project. Then you can abstract business logic into a dll if you want to, but in C++ unless you use COM, it can be a pain ( not sure about MC++ ). You specify that you're building a dll when you create a project.
Christian Graus - Microsoft MVP - C++
|
|
|
|
|
Thank you for the reply.
So I do not want to creat separate forms and then compile them into a dll and use that in the main application. Instead, I should do all the UI work in the same project and use dll's to support them? I think i see what your saying. Thanks Chrisitan your always willing to help out =P
|
|
|
|
|
So pretty much i cant make the ui in several different projects then make them dlls for the main project. I should instead creat all the UI in a single project and use classes in dll's to support them, correct? Thanks for the Help Christian =P
|
|
|
|
|
Anonymous wrote:
So pretty much i cant make the ui in several different projects then make them dlls for the main project. I should instead creat all the UI in a single project and use classes in dll's to support them, correct?
Yes, that's right. I suspect you could put UI stuff in dlls, but it's not the way to go, it stops the forms from dealing with each other, and promotes a fragmented approach where lots of dlls mix business logic and the UI. The point of using dlls is to layer the business logic apart from the UI. More than one dll may make sense if there are different parts to your business logic that have narrow fields of interaction, but the UI is best kept in one place.
Glad to help.
Christian Graus - Microsoft MVP - C++
|
|
|
|
|
Well i have this perfectly terible text type game that, for testing purposes i want to have a DOS version of. (At the moment its just a console app, not DOS compatible)
Here is a sample of the code, and yes its pretty much all like this:
********************************************************************
//The text based carrot game brought to you by me
#include <iostream>
using namespace std;
int main()
{
char a [50];
char b [50];
char c [50];
char d [50];
char e [50];
char f [50];
char g [50];
char h [50];
char i [50];
char j [50];
char k [50];
cout <<"This game was written by Some Guy on forrandomjunk at freewebs\nHELLO and welcom to the CARROT ADVENTURE TRILOGY wich contains all 3 carrot advantures. Enjoy.";
cout <<"\n\nYou are a carrot with no family and no friends and are rather quite lonely, have a look for an inanimate abject to be your new friend, what can you see?\n";
cin.getline (a,50);
cout <<"\n\nCONGRATULATIONS you have found the ";
cout <
|
|
|
|
|
If i get it right, you want to hawe DOS native.
1. .NET framework doesn't support DOS. Command namespace is for framework
2. For cout application use #include <iostrean>
3. Visual Studio will not compile DOS application
4. If you realy want. get DOS c++ compiler, or get like MASM, DASM, TASM assemblers.
|
|
|
|
|
Hi all,
I asked this in another forum but found no answers, so here goes.
What I need to do is store the hex value as a string so I can set a textbox text element to that string. So I'm looking to do something like
System::Byte b = 252;
System::String* s = b (formatted as hex value);
then
textBox1->Text = s;
Does any of that make sense?? 
|
|
|
|
|
Check This sample:
int q;<br />
q = 44;<br />
String *w = String::Format("{0:x}", __box(q));
This is the key for Conversion {0:x}: Zero means first value, x means it vill conver to hex
C++ Syntax to convert from Hex is
int q = 0xfc;
q = 44
Console::WriteLine(w);
Does this help
|
|
|
|
|
Thanx for the reply. What does the _box(q) bit do??
|
|
|
|
|
q is int
But i should pass Object to String::Format so __box does the job
|
|
|
|
|
Ah, that makes things a bit clearer.
Thanx for the help.
|
|
|
|
|
Hi,
I have a problem when I add an unmanaged character array as an member to a managed class. Here's a simple example:
__nogc class Foo
{
public:
static void Test(char* sz)
{}
};
__gc public class Bar
{
public:
void TestFunc1()
{
char buffer[100];
Foo::Test(buffer);
}
char anotherBuffer __nogc[100];
void TestFunc2()
{
Foo::Test(anotherBuffer);
}
};While there's no problem with Bar::TestFunc1, Bar::TestFunc2 won't compile. The error message is error C2664: cannot convert parameter 1 from 'char [100]' to 'char *'. The only difference is that in the first case the char array is allocated on the stack, while in the latter it's a member of the class.. However, if I change the call to
void TestFunc2()
{
Foo::Test(&anotherBuffer[0]);
}
, I get the message error C2664: cannot convert parameter 1 from 'char __gc *' to 'char *'.
Any help is appreciated.
Regards
Thomas
Disclaimer:
Because of heavy processing requirements, we are currently using some of your unused brain capacity for backup processing. Please ignore any hallucinations, voices or unusual dreams you may experience. Please avoid concentration-intensive tasks until further notice. Thank you.
|
|
|
|
|
Hello,
I was wondering if the following thing can be managed by using c++.
I have two unmanaged classes. Lets call them A and B. Class B inheritance from A.
A has a method for example ShowMeSomeText() and method B has another method ShowMeSomeMore()
If i want to create a managed wrapper, i will create two new managed classes A and B (ManagedA and ManagedB). ManagedB will have an inheritance of ManagedA.
Inside both classes are declarations of the unmanaged object A and B (so ManagedA has a private declaration of unmanaged object A and the same for ManagedB but with object B)
Now i want create in for example a C# program a new instance of object ManagedB and want to call the method ShowMeSomeText() (which is from the class A). This will not work correctly because ManagedB will call the method from ManagedA but this will use the unmanaged object A and this will go wrong. How can this be solved?
Hope somebody can help me? Thanx
|
|
|
|
|
Hi,
I am new to C++ & MC++. I am trying to write a wrapper class for exsiting code which uses libraries(Adobe Framemaker) to open documents. These libraries are written in C++.
The code is :-
......
public __gc class Framemaker
{
bool ConnectToFrameSession(String* strProgID)
{
char* strProg = (char*)(void*)Marshal::StringToHGlobalAnsi(strProgID);
ConnectToFrame(strProg);
return true;
}
......
int ConnectToFrame(char *strProg)
{
StringT opt_progid;
CLSID pclsid;
LPOLESTR progStr;
HRESULT res;
F_ObjHandleT docId;
// Get the process name.
opt_progid = F_StrCopyString((StringT)strProg);
// Convert the process name into a GUID
progStr = (OLECHAR*)malloc( WBUFLEN*sizeof(wchar_t) );
if(0 == MultiByteToWideChar(CP_ACP, 0, (char *)opt_progid, -1, progStr, WBUFLEN ))
{
fprintf(stderr, "failed to allocate\n");
return(1);
}
.......
Now the code bombs while doing a malloc or calling any native frame functions in the function above. It says Object Not Set or NullRefernecce Exception.
Is it beacuse i am trying to mix managed and unmanaged code?
How shld i go abt solving ths problem ?
Also this code runs fine if i make a console application & run it.
I am trying to make wrapper dll which would be calkled by C#.
Only differnec i see is __GC.
Pls guide me.
Thanks,
Gurminder
|
|
|
|
|
Is there nobody who can help me on this ?
|
|
|
|
|
Interop is what turns most coders away from Managed C++ .NET. It's complicated and in the case of existing COM and C++ libraries, with lots of User Defined Types (that are often NOT compatible with the Common Language Runtime) involves some extensive marshalling and data manipulation to get things to work adequately.
When you say the code works fine in a console application, does that mean a console app that does NOT have the /clr switch added to the command line? Console apps can be either managed or unmanaged.
When using a native C++ function in a managed application, you must import it using the [DllImport] attribute (which lives in System::Runtime::InteropServices, and you must include this namespace in your code or use fully qualified names).
You might want read this:
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpguide/html/cpconconsumingunmanageddllfunctions.asp[^]
|
|
|
|
|
Thanks for replying.
But my problem persists.
Actually I have tried both ways. One using PInvoke & the other using Managed Wrappers. In both the approaches, I am able to enter the unmanaged function, pass data. But, moment I call the frame APIs or try using new, malloc etc it bombs throwing NullRefernceExcpetion.
In the console applictaion, I complied it using /clr.
I run it & it interacts with the framemaker perfectly.
Frame maker APIs are written in C/C++.
My objective is to call the Framemaker APIs from C#.
What is the best way to this ?
What i belive is that i can get a resoltuion if i m successful in migrating the EXE as a .Net Dll. But, I have tried both ways & I am not able to go ahead because of the issue.
I read it on the net that such exceptions could be raised by something called as Access Violations in the unmanaged code. But, I dont know how to resolve it.
|
|
|
|
|
Some suggestions:
I am unfamiliar with the Adobe Framemaker DLLs, but I'm guessing they are COM libraries. Generally, when you get a NullReferenceException, as you no doubt are aware, you failed to correctly instatiate the COM object or Interface that you must obtain (by calling Query Interface) in order use the method. In your code, you could handle the exception by outputting the exception to a message box or something similar.
malloc is deprecated in C++, and should NOT be used in .NET (although you can use the appropiate headers that define the malloc memory allocator) it is not recommended. Instead use the new operator to instantiate objects, and then -> pointer syntax to invoke methods.
If you are dealing with a COM type library, try using the TlbImp.exe that is included with the Framework SDK and the .NET Framework install. This utility will convert a type library into a .NET assembly that can be referenced directly in source code and used as if they were .NET Framework types. You can then examine the types, methods, and all associated elements in the IL Disassembler, which is a great help.
However, none of the above explains why your code would work in a managed console application, and why it would fail in (what I'm assuming is a managed forms application). I'm guessing that you are leaving out some critical piece of information.
|
|
|
|
General 
News 
Suggestion 
Question 
Bug 
Answer 
Joke 
Praise 
Rant 
Admin 
Submit an article or tip
