如下圖所示，顯示三種顏色交替的下拉框。

實(shí)現(xiàn)方法：
1．使用System.Web.UI.HtmlControls控件，把它作為服務(wù)器控件運(yùn)行。
2．在后臺(tái)為這個(gè)select控件綁定數(shù)據(jù)。
3．再調(diào)用一個(gè)自己寫的函數(shù)為它的沒個(gè)項(xiàng)目指定顏色。
實(shí)現(xiàn)代碼（主要實(shí)現(xiàn)部分）：
前臺(tái)（WebForm1.aspx）：
<SELECT id="Select1" style="WIDTH: 300px" name="Select1" runat="server">
<OPTION selected></OPTION>
</SELECT>
后臺(tái)（WebForm1.aspx.cs）：
PRivate void Page_Load(object sender, System.EventArgs e)
{
if(!IsPostBack)
{
SqlConnection cnn = new SqlConnection();
cnn.ConnectionString = "data source=localhost;initial catalog=Northwind;passWord=;"
+"persist security info=True;user id=sa;workstation id=APJ062;packet size=4096";
string sqlstr = "select Top 10 CustomerID, CompanyName from Customers";
cnn.Open();
SqlDataAdapter ad = new SqlDataAdapter(sqlstr,cnn);
DataTable dt = new DataTable();
ad.Fill(dt);
Select1.DataSource = dt;
Select1.DataTextField = "CompanyName";
Select1.DataValueField = "CustomerID";
Select1.DataBind();
BindSelectColor(Select1);
}
}
//為select控件的項(xiàng)目添加樣式
void BindSelectColor(HtmlSelect select) 
{
int num = 0;
string styleString = "";
for(int i = 0 ; i < select.Items.Count; i ++ )
{
num = i % 3;
switch(num)
{
case 0:
{
styleString = "COLOR: #000099; BACKGROUND-COLOR: #F4FAFF";
break;
}
case 1:
{
styleString = "COLOR: #990000; BACKGROUND-COLOR: #FFFAFB";
break;
}
case 2:
{
styleString = "COLOR: #009900; BACKGROUND-COLOR: #F4FFFA";
break;
}
}
select.Items[i].Attributes.Add("style",styleString);
}
}