␡
- How windows manage their text
- Enter GetWindowText
- What if I dont like these rules?
- Can you give an example where this makes a difference?
- Why are the rules for GetWindowText so weird?
This chapter is from the book
This chapter is from the book
This chapter is from the book
This chapter is from the book
Can you give an example where this makes a difference?
CONSIDER THIS CONTROL:
SampleWndProc(...)
{
case WM_GETTEXT:
lstrcpyn((LPTSTR)lParam, TEXT("Booga!"), (int)wParam);
return lstrlen((LPTSTR)lParam);
case WM_GETTEXTLENGTH: return 7; // lstrlen("Booga!") + null
...
}
And application A, which does this:
hwnd = CreateWindow("Sample", "Frappy", ...);
Now consider process B, which gets the handle to the window created by application A (by whatever means):
TCHAR szBuf[80]; GetWindowText(hwnd, szBuf, 80);
This will return szBuf = "Frappy" because it is getting the window text from the special place. However
SendMessage(hwnd, WM_GETTEXT, 80, (LPARAM)szBuf);
will return szBuf = "Booga!"