C#實現的三種方式實現模擬鍵盤按鍵

模擬按鍵在.Net中有三種方式實現。

第一種方式：System.Windows.Forms.SendKeys 

                     組合鍵：Ctrl = ^ 、Shift = + 、Alt = %

模擬按鍵：A

        private void button1_Click(object sender, EventArgs e)
        {
            textBox1.Focus();
            SendKeys.Send("{A}");
        }

模擬組合鍵：CTRL + A

        private void button1_Click(object sender, EventArgs e)
        {
            webBrowser1.Focus();
            SendKeys.Send("^{A}");
        }

SendKeys.Send // 非同步模擬按鍵(不阻塞UI)

SendKeys.SendWait // 同步模擬按鍵(會阻塞UI直到對方處理完訊息後返回)

第二種方式：keybd_event

模擬按鍵：A

        [DllImport("user32.dll", EntryPoint = "keybd_event", SetLastError = true)]
        public static extern void keybd_event(Keys bVk, byte bScan, uint dwFlags, uint dwExtraInfo);

        private void button1_Click(object sender, EventArgs e)
        {
            textBox1.Focus();
            keybd_event(Keys.A, 0, 0, 0);
        }

模擬組合鍵：CTRL + A

        public const int KEYEVENTF_KEYUP = 2;

        private void button1_Click(object sender, EventArgs e)
        {
            webBrowser1.Focus();
            keybd_event(Keys.ControlKey, 0, 0, 0);
            keybd_event(Keys.A, 0, 0, 0);
            keybd_event(Keys.ControlKey, 0, KEYEVENTF_KEYUP, 0);
        }

上面兩種方式都是全域性範圍呢，現在介紹如何對單個視窗進行模擬按鍵

模擬按鍵：A / 兩次

        [DllImport("user32.dll", EntryPoint = "PostMessageA", SetLastError = true)]
        public static extern int PostMessage(IntPtr hWnd, int Msg, Keys wParam, int lParam);

        public const int WM_CHAR = 256;

        private void button1_Click(object sender, EventArgs e)
        {
            textBox1.Focus();
            PostMessage(textBox1.Handle, 256, Keys.A, 2);
        }

模擬組合鍵：CTRL + A

       如下方式可能會失效，所以最好採用上述兩種方式

        public const int WM_KEYDOWN = 256;
        public const int WM_KEYUP = 257;

        private void button1_Click(object sender, EventArgs e)
        {
            webBrowser1.Focus();
            keybd_event(Keys.ControlKey, 0, 0, 0);
            keybd_event(Keys.A, 0, 0, 0); 
            PostMessage(webBrowser1.Handle, WM_KEYDOWN, Keys.A, 0);
            keybd_event(Keys.ControlKey, 0, KEYEVENTF_KEYUP, 0);
        }