请问用C#怎么判断系统的焦点现在在哪个程序上，谢谢了.

Question

C#怎么判断系统的焦点现在在哪个程序上

Answer 1

The GetForegroundWindow function returns a handle to the foreground window (the window with which the user is currently working). The system assigns a slightly higher priority to the thread that creates the foreground window than it does to other threads. SyntaxHWND GetForegroundWindow(VOID);The GetActiveWindow function retrieves the window handle to the active window attached to the calling thread's message queue. SyntaxHWND GetActiveWindow(VOID);

Answer 2

  private void timer1_Tick(object sender, EventArgs e)
        {
            IntPtr _Foreground=GetForegroundWindow();
            int _ProcessID=0;
            GetWindowThreadProcessId(_Foreground, ref _ProcessID);
            System.Diagnostics.Process _Process = System.Diagnostics.Process.GetProcessById(_ProcessID);
            if (_Process == null) return;
            this.Text = _Process.ProcessName +"{"+_Process.MainWindowTitle+"}";
        }        /// <summary>
        /// 获得当前活动窗体句柄
        /// </summary>
        /// <returns></returns>
        [DllImport("user32.dll", CharSet = CharSet.Auto, ExactSpelling = true)]
        public static extern IntPtr GetForegroundWindow();
        /// <summary>
        /// 根据句柄获取进程PID
        /// </summary>
        /// <param name="hwnd">句饼</param>
        /// <param name="lpdwProcessId">引用 返回进程PID</param>
        /// <returns>未知</returns>
        [DllImport("user32.dll")]
        public static extern IntPtr GetWindowThreadProcessId(IntPtr hwnd, ref int lpdwProcessId);
看看行不行~~放个时间控件