新寫的一個委託程式！目的為了鞏固！委託的用法！

代碼如下：public delegate void selectLable(string e);
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
            checkBox1.Enabled = false;
            checkBox2.Enabled = false;
            checkBox3.Enabled = false;
            if (str == "")
            {
                label1.Text = "請輸入字串！";
            }
        }
        public string str { get { return textBox1.Text.ToString(); } set { str = value; } }
       

        private void button1_Click(object sender, EventArgs e)
        {
            if (checkBox1.Checked == true && checkBox2.Checked == false && checkBox3.Checked == false)
            {
                label1.ForeColor = System.Drawing.Color.Red;
            }
            else if (checkBox1.Checked == false && checkBox2.Checked == true && checkBox3.Checked == false)
            {
                label1.ForeColor = System.Drawing.Color.Green;
            }
            else if (checkBox1.Checked == false && checkBox2.Checked == false && checkBox3.Checked == true)
            {
                label1.ForeColor = System.Drawing.Color.Black;
            }
            else
            {
                label1.Text = str;
            }
        }
        public event selectLable onselectLable;
        private void radioButton1_CheckedChanged(object sender, EventArgs e)
        {
            try
            {
                checkBox1.Checked = radioButton1.Checked;
                checkBox2.Checked = false;
                checkBox3.Checked = false;
                if (radioButton1 != null)
                {
                    onselectLable(radioButton1.Checked.ToString());
                }
            }
            catch {
                label1.Text = str;
            }
        }

        private void radioButton2_CheckedChanged(object sender, EventArgs e)
        {
            try
            {
                checkBox1.Checked = false;
                checkBox2.Checked = radioButton2.Checked;
                checkBox3.Checked = false;
                if (radioButton2 != null)
                {
                    onselectLable(radioButton2.Checked.ToString());
                }
            }
            catch {
                label1.Text = str;
            }
          
        }

        private void radioButton3_CheckedChanged(object sender, EventArgs e)
        {
            try
            {
                checkBox1.Checked = false;
                checkBox2.Checked = false;
                checkBox3.Checked = radioButton3.Checked;
                if (radioButton3 != null)
                {
                    onselectLable(radioButton3.Checked.ToString());
                }
            }
            catch {
                label1.Text = str;
            }
          
        }

        private void button2_Click(object sender, EventArgs e)
        {
            try
            {
                radioButton1.Checked = false;
                radioButton2.Checked = false;
                radioButton3.Checked = false;
               
            }
            catch
            {
                str = "資料已經清空！";
                label1.Text = str;
            }
        }
    }

 

介面如下：

 

 

當你點擊取消選擇的時候，你會發現，不用重複的去寫checkBox的狀態，而是直接寫radioButton即可達到清空的目的！這裡輸入框沒清空，抱歉~呵呵~不過很好清空的了！

委託的函數的功能就是在選擇下面的radioButton的時候，上面的checkBox會連動，或許你會說，我直接在radioButton寫誰是 checkBox1.Checked = true;
                checkBox2.Checked = false;
                checkBox3.Checked = false;

何必要checkBox1.Checked = false;
                checkBox2.Checked = false;
                checkBox3.Checked = radioButton3.Checked;
                if (radioButton3 != null)
                {
                    onselectLable(radioButton3.Checked.ToString());
                }

而且還要處理異常！多麻煩啊。等等，朋友，當你多此調用的時候你會回來寫我的，這也就是自己寫時間，調用委託函數的好處。多的就不解釋了！