Read and write in file

[cpvc]

Hi I more problem when new is came then old line is delete.But i don't want to delete old line..Plz help me

[toxcct]

cpvc++ wrote:

Plz help me

F*CK, you don't reply to my questions, and still you're asking for help ?!!! :mad:

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[cpvc]

Hey what question Man?I am asking first time..

[toxcct]

Does this post mean something to you ?[^]

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[cpvc]

Mr. toxcct

I am not Mr. polop which is start this thread.I am different user and it's post help me and i want some more help me..Sorry for missunderstanding any way my code is here..Pla help me

CStdioFile file;
if (file.Open("\\log.txt", CFile::modeCreate|CFile::modeWrite ))
{
file.WriteString(logfile);

	file.WriteString("\\n");
	
}
file.Close();

logfile is CString type which have some information.. Now i am able to write in file but old line is delete when new line write. Plz help me

[toxcct]

cpvc++ wrote:

I am not Mr. polop which is start this thread

sorry, I didn't notice that aspect of the things :) The problem in your code is that you're using CFile::modeCreate, but according to the documentation[^], this flag tells to truncate the file if already existing :

MSDN says:

CFile::modeCreate Directs the constructor to create a new file. If the file exists already, it is truncated to 0 length

So, you have to add the flag CFile::modeNoTruncate to counter this undesired behavior. The use of this flag however keeps the file pointer at the beginning of the file. So if you want to append things at the end, you must call once after CStdioFile::Open() the function CStdioFile::Seek(CFile::end). Does the following work better ?

CStdioFile file;
if (file.Open(_T("\\log.txt"), CFile::modeCreate | CFile::modeWrite | CFile::modeNoTruncate)) {
//file.Seek(0, CFile::end);
file.SeekToEnd();
file.WriteString(logfile);
file.WriteString(_T("\n"));
file.Close();
}

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modified on Thursday, September 4, 2008 6:46 AM

[cpvc]

ok when i am useing your code then i am geting error..Plz help me

error C2660: 'CStdioFile::Open' : function does not take 1 arguments
error C2660: 'CStdioFile::Seek' : function does not take 1 arguments
error C2065: 'logfile' : undeclared identifier1>
error C2660: 'CStdioFile::Open' : function does not take 1 arguments
error C2660: 'CStdioFile::Seek' : function does not take 1 arguments
error C2065: 'logfile' : undeclared identifier

[toxcct]

god, I made a typo. you shouldn't have read

if (_T(file.Open("\\log.txt"), CFile::modeCreate | CFile::modeWrite | CFile::modeNoTruncate)) {

but this :

if (file.Open(_T("\\log.txt"), CFile::modeCreate | CFile::modeWrite | CFile::modeNoTruncate)) {

I fixed the previous post BTW. and sorry, I am at work, and I have no compiler, so I couldn't test it before posting...

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[cpvc]

i was read but i think both have make same mistake..And mistake is

file.Seek(CFile::end)

this is not right and right one is this

file.Seek(0,CFile::end)

Any way thxs for help..

[toxcct]

cpvc++ wrote:

this is not right and right one is this file.Seek(0,CFile::end)

Yes you're right. BTW, you still can call CFile::SeekToEnd() which takes no parameters, and moves directly to the end of file. anyway, does it work now for you ?

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