🚀 go-pugleaf

I think your problem is in this line:
cds.lpData=AnsiStringToSend.c_str();
AnsiString does some memory management in  the background and might change
the memory location of the data. I believe I have seen some reference in the
help files about this. what c_str() returns is only valid if it is passed to
another function on the stack. BCB does not guarantee the pointer returned
by c_str() will remain valid after that. please look at the example in the
help file for c_str() function

Sam





"Boba" <Boba@somewhere.world> wrote in message
news:4147428c@newsgroups.borland.com...
> Hallo,
> I use the WM_COPYDATA message to send the AnsiString content
> between TApplications. Once in a while (I'd say <10% cases)
> the string will arrive corrupt at the end. Are there any
> special considerations regarding usage of this message for
> data exchange? or should I ask in .components.using NG ?
> Here's what I do:
>
> //sending:
> COPYDATASTRUCT cds;
> cds.dwData=1;//number of strings to be sent
> cds.cbData=AnsiStringToSend.Length();//<1024
> cds.lpData=AnsiStringToSend.c_str();
> ::SendMessage(hWndOfReceiver,WM_COPYDATA, 0,(LPARAM)&cds);
> //reciving:
> char buff[1024];
> ::ZeroMemory(buff,sizeof(buff));
> ::CopyMemory(buff,Msg.CopyDataStruct->lpData,Msg.CopyDataStruct->cbData);
> //where Msg is of ref. to TWMCopyData type
> AnsiString s=AnsiString(buff);
> ShowMessage(s);//some strings get corrupt. Why?
>
> Please help. Boba.
>
>
>