KeyDown事件的用法！！！

Question

 private void Form1_KeyDown(object sender, KeyEventArgs e)
        {
            try
            {
                if (e.KeyCode.Equals(this.label1.Text))
                {
                    this.label1.Top = 0;
                    this.label1.Left = R.Next(5, 200);
                    char ch = Convert.ToChar(R.Next(65, 91));
                    this.label1.Text = ch.ToString();
                    count1++;
                }
                else if (e.KeyCode.Equals(this.label2.Text))
                {
                    this.label2.Top = 0;
                    this.label2.Left = R.Next(60, 200);
                    char ch = Convert.ToChar(R.Next(65, 91));
                    this.label2.Text = ch.ToString();
                    count1++;
                }
                else if (e.KeyCode.Equals(this.label3.Text))
                {
                    this.label3.Top = 0;
                    this.label3.Left = R.Next(115, 200);
                    char ch = Convert.ToChar(R.Next(65, 91));
                    this.label3.Text = ch.ToString();
                    count1++;
                }
                else if (e.KeyCode.Equals(this.label4.Text))
                {
                    this.label4.Top = 0;
                    this.label4.Left = R.Next(170, 200);
                    char ch = Convert.ToChar(R.Next(65, 91));
                    this.label4.Text = ch.ToString();
                    count1++;
                }
                else if (e.KeyCode.Equals(this.label5.Text))
                {
                    this.label5.Top = 0;
                    this.label5.Left = R.Next(225, 200);
                    char ch = Convert.ToChar(R.Next(65, 91));
                    this.label5.Text = ch.ToString();
                    count1++;
                }
                else if (e.KeyCode.Equals(this.label6.Text))
                {
                    this.label6.Top = 0;
                    this.label6.Left = R.Next(280, 200);
                    char ch = Convert.ToChar(R.Next(97, 122));
                    this.label6.Text = ch.ToString();
                    count1++;
                }
                else if (e.KeyCode.Equals(this.label7.Text))
                {
                    this.label7.Top = 0;
                    this.label7.Left = R.Next(335, 200);
                    char ch = Convert.ToChar(R.Next(97, 122));
                    this.label7.Text = ch.ToString();
                    count1++;
                }
                else if (e.KeyCode.Equals(this.label8.Text))
                {
                    this.label8.Top = 0;
                    this.label8.Left = R.Next(390, 200);
                    char ch = Convert.ToChar(R.Next(97, 122));
                    this.label8.Text = ch.ToString();
                    count1++;
                }
                else if (e.KeyCode.Equals(this.label9.Text))
                {
                    this.label9.Top = 0;
                    this.label9.Left = R.Next(445, 200);
                    char ch = Convert.ToChar(R.Next(97, 122));
                    this.label9.Text = ch.ToString();
                    count1++;
                }
                else if (e.KeyCode.Equals(this.label10.Text))
                {
                    this.label10.Top = 0;
                    this.label10.Left = R.Next(500, 200);
                    char ch = Convert.ToChar(R.Next(97, 122));
                    this.label10.Text = ch.ToString();
                    count1++;
                }
            }
            catch
            {            }
        }
这是做打字游戏的键盘监听事件的代码，为什么运行后按键盘屏幕上下落的字符消不掉呢？
小弟急用，在此先谢过了！！！

Answer 1

先在formload事件里写句代码        private void Form1_Load(object sender, EventArgs e)
        {
            this.KeyPreview = true;
        }

Answer 2

也可以直接在form的属性里改这个KeyPreview 为true