给另一个进程的编辑框写入字符串

        POINT point;
        if(TRUE == ::GetCursorPos(&point)){  // 获取系统光标位置
            HWND hWnd = ::WindowFromPoint(point);      // 获取光标位置的窗口句柄
            if(hWnd){
                ::SendMessage(hWnd, WM_CHAR, 'a', 1);        // 向该窗口写入字符
                ::SendMessage(hWnd, WM_CHAR, 'b', 1);
                ::SendMessage(hWnd, WM_CHAR, 'c', 1);
                ::SendMessage(hWnd, WM_CHAR, 0x0a, 1);
            }
        }