alttab.py 文件源码

def get_window_text(hwnd):
        """
        Wrapper over the GetWindowTextW() Win32 function
        Raises a OSError exception on error.
        """
        length = ctypes.windll.user32.GetWindowTextLengthW(hwnd)
        buff = ctypes.create_unicode_buffer(length + 1)
        ctypes.windll.kernel32.SetLastError(0)
        res = ctypes.windll.user32.GetWindowTextW(hwnd, buff, length + 1)
        if not res and ctypes.GetLastError() != 0:
            raise ctypes.WinError()
        return buff.value