C#实现的三种方式实现模拟键盘按键

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

        private void button1_Click(object sender, EventArgs e)
        {
            webBrowser1.Focus();
            SendKeys.Send("^{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);
    }</pre> 模拟组合键：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);
    }</pre> 上面两种方式都是全局范围呢，现在介绍如何对单个窗口进行模拟按键 
 
 
 
 模拟按键：A / 两次 
 
 
        [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);
    }</pre> 
 
 
 
 模拟组合键：CTRL + A 
        如下方式可能会失效，所以最好采用上述两种方式 
 
 
        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);
    }</pre>