第一步先上页面上托一个dropdownlist控件
前台
<asp:DropDownList ID="DropDownList1" runat="server">
</asp:DropDownList>
</asp:DropDownList>
后台
先写一个返回dataset的方法
///<summary>
/// 绑定dropdownlist信息
///</summary>
///<returns></returns>
public DataSet Drop()
{
using (SqlConnection conn =new SqlConnection(ConfigurationManager.ConnectionStrings["learning"].ConnectionString))
{
conn.Open();
using (SqlCommand cmd = conn.CreateCommand())
{
cmd.CommandText ="select ExamName from ExamMain group by ExamName order by ExamName";
SqlDataAdapter adapter =new SqlDataAdapter(cmd);
DataSet ds =new DataSet();
adapter.Fill(ds);
return ds;
}
}
}
/// 绑定dropdownlist信息
///</summary>
///<returns></returns>
public DataSet Drop()
{
using (SqlConnection conn =new SqlConnection(ConfigurationManager.ConnectionStrings["learning"].ConnectionString))
{
conn.Open();
using (SqlCommand cmd = conn.CreateCommand())
{
cmd.CommandText ="select ExamName from ExamMain group by ExamName order by ExamName";
SqlDataAdapter adapter =new SqlDataAdapter(cmd);
DataSet ds =new DataSet();
adapter.Fill(ds);
return ds;
}
}
}
调用绑定方法
publicvoid DataDropDownList()
{
//数据源
this.DropDownList1.DataSource = Drop();
//要绑定的字段
this.DropDownList1.DataValueField = Drop().Tables[0].Columns["ExamName"].ColumnName;
// 显示的值
this.DropDownList1.DataTextField = Drop().Tables[0].Columns["ExamName"].ColumnName;
this.DropDownList1.DataBind();
}
{
//数据源
this.DropDownList1.DataSource = Drop();
//要绑定的字段
this.DropDownList1.DataValueField = Drop().Tables[0].Columns["ExamName"].ColumnName;
// 显示的值
this.DropDownList1.DataTextField = Drop().Tables[0].Columns["ExamName"].ColumnName;
this.DropDownList1.DataBind();
}