comboBox获取value中的值

private void comboBox2_SelectedIndexChanged(object sender, EventArgs e)
    {
        string a = ((ComboBoxItem)comboBox2.SelectedItem).Value;
        textBox2.Text = a;
    }

    private void Form1_Load(object sender, EventArgs e)
    {
        ComboBoxItem i1 = new ComboBoxItem();
        i1.Text = "this is i1";
        i1.Value = "001";
        ComboBoxItem i2 = new ComboBoxItem();
        i2.Text = "this is i2";
        i2.Value = "002";

        comboBox2.Items.Add(i1);
        comboBox2.Items.Add(i2);

        comboBox2.DisplayMember = "text";
        comboBox2.ValueMember = "value";        

         
    }
    public class ComboBoxItem
    {
        private string m_Text;
        private string m_Value;
        public ComboBoxItem()
        {
            this.m_Text = String.Empty;
            this.m_Value = String.Empty;
        }
        public string Text
        {
            get { return this.m_Text; }
            set { this.m_Text = value; }
        }
        public string Value
        {
            get { return this.m_Value; }
            set { this.m_Value = value; }
        }
        public override string ToString()
        {
            return this.m_Text;  //最关键的
        }  
    }

ComboBox的Items不能添加Value

不想用绑定的话,自已写一个实现Value和Text属性的类,然后重写ToString()方法,并返回和Text属性一样的值,然后把这个类的实际Add到ComboBox.Items中,取值时再转换一下类型.   
  当你往ComboxBox的Item中扔一个任意object时,显示出的内容就是这个object的ToString()方法.所以必须重写ToString()方法,来显示你要显示的内容.