Re: Cstring WriteString not working also write not working
If you want to read and write to the same file you're going to have to
remember the beginning of the line you are reading and move the file
pointer back to that spot before overwriting the line. You'll also have to
remember the length of the line and make sure the new line is exactly the
same length (perhaps you could fill with spaces).
I side with the others on this one. I'd read the old file and write the
lines to a temp file until getting to the one I want to change then write
the new line, then get the rest of the old file. After closing the old and
new files you can delete the old one and the rename the new one.
Here is a routine for making a temp filename:
CString GetTempFilePath(LPCTSTR strPattern)
{
CString csPath;
if(GetTempPath(_MAX_PATH,csPath.GetBuffer(_MAX_PATH+1)) != 0) {
csPath.ReleaseBuffer();
CString csTempFile;
if(GetTempFileName(csPath,strPattern,0,csTempFile.GetBuffer(_MAX_PATH+1))
!= 0) {
csTempFile.ReleaseBuffer();
return csTempFile;
}
}
return CString();
}
CString csTempFile = GetTempFilePath(_T("XXX")); // Temp XXX path
Tom
"zack" <zack@discussions.microsoft.com> wrote in message
news:AB723EF4-CB8F-45BE-9CED-4B3DA9736037@microsoft.com...
Hi I am trying to cahnge one line in a TXT file (log file of my
application),
the TXT file already include many line and i try to recognize the line i
need and then update it with the string i need,
But WriteString looks like it finish fine no fail,
But the TXT file doesn't change .
Here is the code:
CString readLine,CompareResultFile="c:\a.txt";//the file path is just an
example
CStdioFile LogFile_CStdioFile;
char * full_Log_file_path= (char*)malloc (_MAX_PATH);
int numLines=0;
TCHAR PASS_test[] = _T("Result: PASS");
TCHAR FAIL_test[] = _T("Result: FAIL");
if (!LogFile_CStdioFile.Open(CompareResultFile, CFile::modeReadWrite ))
{
return FALSE;
}
while(LogFile_CStdioFile.ReadString(readLine) )
{
sprintf(full_Log_file_path,"%S",readLine.GetBuffer(0));
if(strncmp(full_Log_file_path,"Result:",7))
{
numLines++;
continue;
}
else
{
if(Status)
{
LogFile_CStdioFile.WriteString(PASS_test);
}
else
{
LogFile_CStdioFile.WriteString(FAIL_test);
}
break;
}
}
LogFile_CStdioFile.Close();
I need suggestion what is the best way to update one line?