WinAPI: GetWindowTextLength - 获取窗口标题长度

//声明:
GetWindowTextLength(
  hWnd: HWND {窗口句柄}
): Integer;  {返回窗口标题长度}


//举例:
var
  i: Integer;
begin
  i := GetWindowTextLength(Self.Handle);
  ShowMessage(IntToStr(i));
end;