提一个关于ComboBox的问题?
在网页上有个下拉表单: 
  <select>  
  <option   value= "值 "> text </option>  
  </select>  
 我们能看到的是 <option> 项的text,选择这项就可以得到value= "值 "。   
 相对应的C#   Form里面的ComboBox控件是 
 我们看到的是Items.Text属性,但是它每项所对应的value属性怎么赋值了?
------解决方案--------------------this.cmbSno.DataSource=ds.Tables[ "student "]; 
 this.cmbSno.DisplayMember= "Sno "; 
 this.cmbSno.ValueMember= "Sno ";
------解决方案--------------------绑定时指定DisplayMember和ValueMember..   
 for example:   
 一个表studentDetails,两个字段(sno,sname),绑定到Commbobox:   
 //FormLoad时绑定,显示姓名 
 private void Form1_Load(object sender, EventArgs e) 
         { 
             SqlConnection con = new SqlConnection( "server=.;database=student;uid=sa;pwd=0421 "); 
             SqlDataAdapter sda = new SqlDataAdapter( "select * from studentDetails ", con); 
             DataSet ds = new DataSet(); 
             sda.Fill(ds,  "student "); 
             this.comboBox1.DataSource = ds.Tables[ "student "]; 
             this.comboBox1.DisplayMember =  "sname "; 
             this.comboBox1.ValueMember =  "sno "; 
         } 
 //得到当前选中项的value,即学号 
 private void comboBox1_SelectedValueChanged(object sender, EventArgs e) 
         { 
             this.textBox1.Text = this.comboBox1.SelectedValue.ToString(); 
         }