WinForm 窗体鼠标消息 up， down， click， doubleclick 响应先后顺序测试

事件响应及处理顺序：
单击事件：
down--------click-------up---
双击事件：
down---------click------up-----down-----doubleclick----up----

测试代码如下：

 public partial class Form1 : Form
    {
        string a = "";
        Thread d;
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            this.button2.Text = Thread.CurrentThread .ManagedThreadId.ToString ();
            d = new Thread(new ThreadStart(this.doa));
            d.Start ();
            MessageBox.Show(a);
        }

        public void doa()
        {
            this.button3.Text = Thread.CurrentThread.ManagedThreadId .ToString();
            this.button1.Text = "woshi";
        }

        private void Form1_MouseClick(object sender, MouseEventArgs e)
        {
           // MessageBox.Show("click");
            a += "click     ";
          // MessageBox.Show(a);
        }

        private void Form1_MouseDoubleClick(object sender, MouseEventArgs e)
        {
           // MessageBox.Show("double click");
            a += "  double click    ";
            MessageBox.Show(a);
        }

        private void Form1_MouseDown(object sender, MouseEventArgs e)
        {
           // MessageBox.Show("down   ");
            a += "down  ";
            //new Form2().Show();
        }

        private void Form1_MouseUp(object sender, MouseEventArgs e)
        {
            a += "up    ";
            //MessageBox.Show("up");
        }
    }