省市级连 采用DropDownList

Question

本帖最后由 x1aoli 于 2011-11-03 22:34:49 编辑

Answer 1

第一个省市下拉框加事件 DropDownList1_SelectedIndexChanged
触发事件后得到第一个下拉的值，在查询到城市的数据 
绑定第二个下拉框

Answer 2

<asp:DropDownList ID="DropDownList1" runat="server" AutoPostBack="True" OnSelectedIndexChanged="DropDownList1_SelectedIndexChanged"></asp:DropDownList><asp:DropDownList ID="DropDownList2" runat="server"></asp:DropDownList>public void Page_Load(object sender,EventArgs e)
{
    if(!IsPostBack)
    {
          this.DropDownList1.DataSource = getDataSet("Province");
          this.DropDownList1.DataTextField= "ProvinceName";
          this.DropDownList1.DataValueField= "ID";
          this.DropDownList1.DataBind();
          this.DropDownList1.Items.Insert(0,"--请选择--");
    }
    
}public void DropDownList1_SelectedIndexChanged(object sender,EventArgs e)
{
        if(this.DropDownList1.SelectedIndex!=0)
        {
              this.DropDownList2.DataSource = getDataSet("City",int.Parse(this.DropDownList1.SelectedItem.Value));
              this.DropDownList2.DataTextField= "CityName";
              this.DropDownList2.DataValueField= "ID";
              this.DropDownList2.DataBind();
        }
} //获取数据集  ,根据你实际的数据库连接字符串进行相应修改
public DataSet getDataSet(string tableName)  
{  
     DataSet ds = new DataSet();  
     using (SqlConnection con = new SqlConnection("Data Source=localhost;uid=sa;pwd=sa;Database=CSDN"))  
      {  
            con.Open();  
            string strSQL = "select * from "+tableName;  
            using (SqlDataAdapter sda = new SqlDataAdapter(strSQL, con))  
            {  
                 sda.Fill(ds);  
            }  
       }  
       return ds;  
 }  public DataSet getDataSet(string tableName,int args)  
{  
     DataSet ds = new DataSet();  
     using (SqlConnection con = new SqlConnection("Data Source=localhost;uid=sa;pwd=sa;Database=CSDN"))  
      {  
            con.Open();  
            string strSQL = "select * from "+tableName+" where PID="+args;  
            using (SqlDataAdapter sda = new SqlDataAdapter(strSQL, con))  
            {  
                 sda.Fill(ds);  
            }  
       }  
       return ds;  
 }  

Answer 3

like this:
http://www.cnblogs.com/insus/archive/2011/07/04/2097059.html