Re: Error in strcpy - C / C++ / MFC Discussion Boards

vikas amin20-Dec-05 3:02

20-Dec-05 3:02

I have function in a class called LoadFile

BOOL Bitmap::LoadFile(const char *FileName)<br />
	{<br />
		<br />
		CFileException e;<br />
		<br />
		strcpy(m_FileName,FileName);<br />
<br />
        }

to which i pass string during the call

const char *FileName= _T("c:\\1.bmp");<br />
BMP.LoadFile (FileName);

there is an error
error: unhandled exception , 0x0000000005 access violation

whats wrong

Vikas Amin
Embin Technology
Bombay
vikas.amin@embin.com

Re: Error in strcpy

khan++20-Dec-05 3:12

khan++

20-Dec-05 3:12

What is m_FileName?
It seems to be something like:
char* m_FileName; //This should produce the error.
However,
char m_FileName[MAX_PATH];//This should not result in an error.
It is unclear from your post; it could be something else also.

this is this.

Re: Error in strcpy

Ted Ferenc20-Dec-05 3:15

Ted Ferenc

20-Dec-05 3:15

What is m_FileName declared as?

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Re: Error in strcpy

RChin20-Dec-05 3:17

RChin

20-Dec-05 3:17

It depends on what data type m_Filename is.
If it is of type CString, then I think this function will not work without first exposing the memory buffer (GetBuffer(0) ??).
If the variable is an array of characters, then it should work (unless the destination size is less than the source string).

I Dream of Absolute Zero

Re: Error in strcpy

toxcct20-Dec-05 3:22

toxcct

20-Dec-05 3:22

vikas amin wrote:
strcpy(m_FileName,FileName);

change to

if ((!m_FileName) && (size_allocated_to(m_FileName) > ::strlen(FileName))) {
    ::strcpy(m_FileName, FileName);
}

TOXCCT >>> GEII power
[toxcct][VisualCalc 2.20][VisualCalc 3.0]

Re: Error in strcpy

vikas amin20-Dec-05 3:29

vikas amin

20-Dec-05 3:29

Ok
I think i got the point
i need to allocate the space for
the destination .

thank you

Vikas Amin
Embin Technology
Bombay
vikas.amin@embin.com

Re: Error in strcpy

Smith#20-Dec-05 3:40

Smith#

20-Dec-05 3:40

see if u have initialized it first. like khan said

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Installing MFC...2% complete

Re: Error in strcpy

Bob Stanneveld20-Dec-05 3:38

Bob Stanneveld

20-Dec-05 3:38

Hello,

You should beware of the UNICODE problems that your code have when you compile with UNICODE defined. See the following where your problems are:

const char* FileName /* ... */ // This declare the normal char string
           = _T("C:\\1.bmp"); // Under UNICODE, this is a w_char* instead of char*

To solve this problem, use TCHAR* instead of char* where you want to use the _T macro.

[EDIT]
You should also use the macros from tchar.h[^] so that you use UNICODE functions when you build with UNICODE defined.
[/EDIT]

Hope this helps.

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... is the police. - Conspiracy brother

Blog[^]

-- modified at 9:43 Tuesday 20th December, 2005

Re: Error in strcpy

Blake Miller20-Dec-05 4:22

Blake Miller

20-Dec-05 4:22

Hey. If m_FileName happens to be a CString, then just do this instead:
mFileName = FileName
instead of using anything like strcpy.

You are LUCKY you got the access violation now and not 10 months from now with 10 million copies of your app in the field WTF | :WTF:

No shirt, no shoes, no brains, no service.

Re: Error in strcpy

toxcct20-Dec-05 4:35

toxcct

20-Dec-05 4:35

it is plainly written that the variables handled are pointers to char (char* and const char*)...

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[toxcct][VisualCalc 2.20][VisualCalc 3.0]

Re: Error in strcpy

Blake Miller20-Dec-05 4:39

Blake Miller

20-Dec-05 4:39

Show me EXACTLY here the m_FileName is defined or declared in his original post?

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Re: Error in strcpy

John M. Drescher20-Dec-05 6:50

John M. Drescher

20-Dec-05 6:50

Since you are using mfc why not use CString and let all this memory allocation for strings automatically be handled for you??

John

Re: Error in strcpy

David Crow20-Dec-05 10:29

David Crow

20-Dec-05 10:29

vikas amin wrote:
strcpy(m_FileName,FileName);

Why are you not using CString?

"Take only what you need and leave the land as you found it." - Native American Proverb

Re: Error in strcpy

ThatsAlok20-Dec-05 18:19

ThatsAlok

20-Dec-05 18:19

vikas amin wrote:
strcpy(m_FileName,FileName);

Hai Vikas,
what type of variable is m_FileName

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cheers,
Alok Gupta
VC Forum Q&A :- I/ IV

Initializing Structure in a class

vikas amin20-Dec-05 2:45

vikas amin

20-Dec-05 2:45

I have a class in which there is a structe
i want to initialize the structre through the constructer .

class xyz{

struct tagBITMAPFILEHEADER
{
WORD bfType; // must be 'BM'
DWORD bfSize; // size of the whole .bmp file
WORD bfReserved1; // must be 0
WORD bfReserved2; // must be 0
DWORD bfOffBits;
}m_BITMAPFILEHEADER ;

xyz()
{
BITMAPFILEHEADER ={0,0,0,0,0};
}

}

I am getting an error
error C2059: syntax error : '{'
error C2143: syntax error : missing ';' before '{'

am i wrong someware

}

Vikas Amin
Embin Technology
Bombay
vikas.amin@embin.com

Re: Initializing Structure in a class

Russell^'20-Dec-05 2:55

Russell^'

20-Dec-05 2:55

If the code that you post is the real code there is a little error:

vikas amin wrote:
xyz()
{
BITMAPFILEHEADER ={0,0,0,0,0};
}

xyz()
{
m_BITMAPFILEHEADER ={0,0,0,0,0};
}

Have a nice code day Wink | ;)

Re: Initializing Structure in a class

toxcct20-Dec-05 3:02

toxcct

20-Dec-05 3:02

and a ; missing after the closing } of the class... Wink | ;)

TOXCCT >>> GEII power
[toxcct][VisualCalc 2.20][VisualCalc 3.0]

Re: Initializing Structure in a class

vikas amin20-Dec-05 3:09

vikas amin

20-Dec-05 3:09

Sorry that was not the real code it is not copy pasted
i typed it again .

The real problem is how to initialise the structure .
Can anyone tell me

Vikas Amin
Embin Technology
Bombay
vikas.amin@embin.com

Re: Initializing Structure in a class

toxcct20-Dec-05 3:13

toxcct

20-Dec-05 3:13

edit your previous post and put the code between <pre></pre> tags...

TOXCCT >>> GEII power
[toxcct][VisualCalc 2.20][VisualCalc 3.0]

Re: Initializing Structure in a class

Russell^'20-Dec-05 3:20

Russell^'

20-Dec-05 3:20

Why don't use

xyz()
{
m_BITMAPFILEHEADER.bfType=0;
m_BITMAPFILEHEADER.bfSize=0;
m_BITMAPFILEHEADER.bfReserved1=0;
m_BITMAPFILEHEADER.bfReserved2=0;
m_BITMAPFILEHEADER.bfOffBits=0;
}

Because, I don't remember if you could use ={0,0,0,0,0} in that point

Have a nice code day Wink | ;)

Re: Initializing Structure in a class

Blake Miller20-Dec-05 4:26

Blake Miller

20-Dec-05 4:26

My favorite,
ZeroMemory(m_BITMAPFILEHEADER, sizeof(m_BITMAPFILEHEADER));
if you want to set everything to 0.

Does not work if a class with complex objects is embedded wihtin the structure, such as a CString, however.

I can't believe how many times I have seen code setting data structure's fields to all zeroes, when there are several dozen fields, instead of block setting the entire element. If I only had a dollar... Sigh | :sigh:

No shirt, no shoes, no brains, no service.

Re: Initializing Structure in a class

Russell^'20-Dec-05 4:37

Russell^'

20-Dec-05 4:37

I understand you!!!
This happens, really, too many times. Frown | :(

Have a nice code day Wink | ;)

Implementing Doc/View/Frame in an ActiveX control

zulat20-Dec-05 2:21

zulat

20-Dec-05 2:21

Hi everybody,

I need to implement Doc/View/Frame in an ActiveX control. I have tried to copy the code from a standart MFC Wizard generated SDI application in a standart Wizard generated ActiveX control, but it didnt work - all I could get was a bunch of crashes (for the document, I derived my class from COleDocument). Can anybody point me in the right direction. Any information is appreciated.

Thanks in advance,
Dennis.

changing background color of messagebox windows,menu

_kane_20-Dec-05 1:17

_kane_

20-Dec-05 1:17

hello,

i changed the background color of my dialogs in a dialog based MFC app by adding the following code:

SetDialogBkColor(RGB(150, 150, 150), RGB(0, 0, 0));

in my dialog based applications "Initinstance". However though the dialogs have all changed color, the background color of MessageBox() has not, and also the menu Button (Like File, Edit, Help) bar still follows the windows theme color. The menu options however show in white which is fine. I just want to change the background color of my messagebox and the color of my top menu.

Any pointers on how to do this?

"Some guys hack just to get themselves a girlfriend.What a pathetic reason huh ?"

bitmapped title/caption bar in MFC

_kane_20-Dec-05 1:08

_kane_

20-Dec-05 1:08

Hi,
can anyone tell me how to use a bitmap as a background for my title bar? I have used a bitmap background for the dialogs and the title bar looks very out of place.
thankx Smile | :)

"Some guys hack just to get themselves a girlfriend.What a pathetic reason huh ?"

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