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Neville Franks...
Thank you.
Neville Franks wrote:
I might be able to if you explain what the problem is.
It calls the ctors and dtors autometically.
(* Sorry for asking you before chacking  *)
But 1 question remaining: Why/How Come automatically?
=-=-=-=-=-=-=-=
:rose The Server
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The_Server wrote:
But 1 question remaining: Why/How Come automatically?
Because that is what the C++ Language spec says operator new does. ie. It allocates memory and then calls the ctor.
"Who deleted my pointer?" may be of interest:
http://www.codeproject.com/debug/newdel.asp[^]
Neville Franks, Author of ED for Windows. Free Trial at www.getsoft.com
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Use what you said, the program crashed... 
BuggyMax
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Hi there, this is what you want ...
#include <iostream><br />
<br />
<br />
static void* operator new( unsigned int cb )<br />
{<br />
std::cout << "My new \n";<br />
<br />
return (void*)0;<br />
}<br />
<br />
void __cdecl operator delete(void *p)<br />
{<br />
std::cout << "My delete. \n";<br />
}<br />
<br />
void main()<br />
{<br />
char* p = new char[3];<br />
<br />
delete [] p;<br />
}<br />
<br />
<br />
BuggyMax
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What is the include file? Code posting rule one - Use the Formatting bar.
Why is new static and not __cdecl and delete isn't static but is __cdecl? 
According to "More Effective C++" by Scott Meyers, "the first parameter to operator new must always be size_t." MSDN docs also show this.
Neville Franks, Author of ED for Windows. Free Trial at www.getsoft.com
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Neville Franks wrote:
What is the include file? Code posting rule one - Use the Formatting bar.
1) The include file is merely <iostream> , there's no ".H" extension.
Including iostream is just for output strings (cout). For information about the new-styled include, please refer to ISO C++, the third generation of C++ programming language. If you just want to trace into step-by-step without displaying some msg on screen, you don't have to include iostream.
2) Yes I did. I used the "code" formatting (on top of the green face button, " " ). But it seemd make my code red-colored but not well-format... 
Neville Franks wrote:
Why is new static and not __cdecl and delete isn't static but is __cdecl?
1) Well, I traced into a normal new operator to look at what the prototype that VC++6 uses in file <new>. I saw it is :
void *__cdecl operator new(size_t) _THROW1(std::bad_alloc);
2) static, inline, and __cdecl are three different things.
You may have already know what static and inline mean.
__cdecl is just a hint to make the compiler know how to deal with the stack and formal arguments.
Default calling convention VC++ uses is __cdecl. But you can change it by finding the setting:
Project - Settings - C/C++ tab - calling conventions.
3) Why void* crashes but static void* runs, ... to tell the truth, I do not know. Just now I looked at some web pages discussing overloading global operator new, all of them say void* . I don't find any talking about void* crashing the program with VC++6.
Maybe the one without "static" runs with your VC++.NET. I do not know. I don't have a VC++7 or 7.1.
4) size_t is just a concept of "number that you count". For example, one variable, two variables, three variables...
Since the basic type of "number that you count" is integer, and there is no such " -1 apple, -2 apples ... ", size_t therefore is defined as "unsigned int"...
BuggyMax
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I'm looking for the functionality that was in Visual c++ 6.0 under 'View->Resource includes' where you could add a resource header and .rc file from a static library that should be linked into the application. I cannot find it anywhere  Does anyone know? Thanks.
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I hate it when that happens: search for something a few hours, ask on forums, find it a few minutes later For who wants to know: resource view, right-click on .rc file name, "Resource Includes..."
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Hi
i have a CListCtrl which contains a list of names, but there
are duplicates in them, i need a function to remove them
ne1 ne ideas ??? 
thanks
si
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something like this:
bool bIdExists = false;<br />
CString strIdListTemp = "";<br />
<br />
<br />
for(int i = 0; i< m_messageList.GetItemCount(); i++)<br />
{<br />
CString strIdList = m_messageList.GetItemText(i, 4); <br />
if( strIdList == m_yourDuplicateStr)<br />
{<br />
strIdListTemp = strIdList;<br />
bIdExists = true;<br />
}<br />
}<br />
<br />
if(bIdExists)<br />
{<br />
CString temp = "";<br />
temp.Format("Str: %s already exists", strIdListTemp);<br />
AfxMessageBox(temp);<br />
}<br />
else<br />
{<br />
}
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Maybe your design dictates differently, but rather than remove them after the fact, why not be proactive and prohibit them from being added in the first place?
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How do you know the file is being opened, you aren't bothing to even test for this or any other errors. STRANGE CODE.
How do you know the file is being written correctly? Have you verified that m_hfDCMedianArray[] contains what you think it contains?
The for() loop isn't displayed correctly. You need to use the pre & code & < & > formatting options when posting.
Neville Franks, Author of ED for Windows. Free Trial at www.getsoft.com
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I have hosted WebBrowser in my application. (CHtmlCtrl).
Sometimes (i can't find out when), but not always, after navigation is complete,
window containing browser is activated and get focus.
How to avoid this activation ?
Thank you
rrrado
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Hello!
I Deveoped a Program.
that program is draw a many object(circle, image, rectangle, text, etc)
i ran that program in debugging mode but that program is stop.
stop code is below...
[Header File]
char text[256];
[CPP File]
void Class::Draw(CDC* pDC)
{
// text have a value. value is "OPEN"
...
...
CString strText = _T("");
strText = text;
int nFind = strText.Find('.'); ===> Run is Stop
...
...
}
but i run that program continuously use a F5 Key.
then that program is run (not have problem...)
i don't know why happened that problem...
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i think problem will be one line above.
char text[] should be TCHAR [] (to work in unicode build).
What does contain text ? is it correctly null terminated string ?
rrrado
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Suppose I need to make a generic class and use "void* m_pData" to store pointer to an object, of which the data type is unknown at compiling time. In the destructor I want to free the memory, is it safe to use "delete m_pData"? Thanks.
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sure it is, delete does not know anyway, how did you declare that pointer
rrrado
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Contrary to an earlier reply, I would say NO.
If you think about delete, it is actually a two stage process.
1) Call the destructor.
2) Give the memory back.
deleteing a void pointer may do a free on the memory, thus completing stage 2,
but the compiler wouldn't have a clue as to which destructor (if any) to call. At
best you would not completely dismantle the class (imagine if it had pointers to other
allocated memory...)
If you really wanted a generic delete, then have a very basic class
that all of your generics inherit from:
class GenericBase
{
public:
virtual ~GenericBase () {}
};
class Specific : public GenericBase
{
};
And use a GenericBase * in place of the void * in your code. The virtual
destructor means any inheriting class have a vtable and thus will have their (or ancestor
classes) destructor called as well.
I feel all "Matt Pietrik"y!
Iain.
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That solves my problem. Thank you.
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oh, you're right 
<ashamed>
rrrado
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Can anyone help me with the following problem? I have the following classes:
[code]
//DMR.h file
template <class t="">
class DMR
{
public:
static T* New();
...
};
class foo : public DMR<foo>
{
public:
...
};
//main.cpp file
#include “DMR.h”
int main()
{
foo::New();
return 0;
}
[/code]
Trying to execute this code I get a linking error for unresolved symbol. More specifically I get this:
DDK error LNK2019: unresolved external symbol "public: static class foo * __cdecl DMR<class foo="">::New(void)" (?New@?$DMR@Vfoo@@@@SAPAVfoo@@XZ) referenced in function _main
Any idea of what I ‘m doing wrong?
Thank you, Themis
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First of all, the linker is right, you have never (in the sample you gave) written a
T* DMR::New ()
{
T *t = new T;
t->DoSomething ();
return t;
}
function.
While I am no great expert on templates (since I found they don't work with __declspec() I'm
not so keen) I think you have another error. You never do the <> thing to specify the type of
T you are using. Maybe you actually mean:
class foo
{
void DoSomething ();
};
int main ()
{
DMR<foo> f;
f.New ();
return 0;
}
Or was I misunderstanding your intent?
Iain
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I forgot to mention that I 've written the body T* DMR::New(), so this is not the problem.
My intent is to create new instances of the foo class using the New method of DMR. I use the template superclass in order to be able to implement it later on another class, let's say yak class.
Themis
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My misunderstanding.
There are (not unreasonably) problems inheriting static functions. I presume you have templated the
DMR class to get around these. From the linker error, the compiler has implicitly assumed a
static foo * foo::New () function which you haven't implemented. Which probably brings you back
to square one again...
Just a thought... You may be able to create an non-static operator new in class DMR which
would be inherited. Probably! You are delving into the nasty bit of C++...
I'd be tempted to go back to the drawing board and see what your New function is doing. Maybe you
could just do it in the DMR::DMR () function.
There are usually several ways of achieving the same result. Maybe you've just picked the hard way!
Iain.
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Hi,
How can I get the file list of a directory?
like CListbox::dir but directly.
thanks
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