data binding

Hi johny,


<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="Cascading_dropdownlist._Default" %>





   


   

   

   
   
  
       
          
                              ForeColor="Red" Width="150px">
                                 AppendDataBoundItems="true"  runat="server" Height="20px" Width="156px"
                    Font-Bold="True"
                   ForeColor="#FF9900"
                   onselectedindexchanged="ddlProduct_SelectedIndexChanged">
           
       

     
      
     
  
       


       
    
                  ForeColor="Red" Width="150px">
                    AppendDataBoundItems ="true"  runat="server" Height="20px"
Width="155px"  Font-Bold="True"
             ForeColor="#993300">
      
    
    
       
       
    
   

   

using System;
using System.Collections;
using System.Configuration;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Linq;
using System.Data.SqlClient;
namespace Cascading_dropdownlist
{
    public partial class _Default : System.Web.UI.Page
    {
        string strConnString = ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString;
        string str;
        SqlCommand com;
        SqlDataAdapter sqlda;
        DataSet ds;

        protected void Page_Load(object sender, EventArgs e)
        {
            if (!IsPostBack)
            {
                product();
            }
        }
        void product()
        {
        SqlConnection con = new SqlConnection(strConnString);
        con.Open();
        str = "select Productid,Productname from TVOP1";
        com = new SqlCommand(str, con);
        sqlda = new SqlDataAdapter(com);
        ds = new DataSet();
        sqlda.Fill(ds, "TVOP1");
        ddlProduct.Items.Clear();
        ddlProduct.Items.Add("--Select--");
        ddlProduct.DataValueField = "Productid";
        ddlProduct.DataTextField = "Productname";
        ddlProduct.DataSource = ds;
        ddlProduct.DataMember = "TVOP1";
        ddlProduct.DataBind();
        con.Close();
        }

        protected void ddlProduct_SelectedIndexChanged(object sender, EventArgs e)
        {
            productsub();
        }
        void productsub()
        {
        SqlConnection con = new SqlConnection(strConnString);
        con.Open();
        str = "select Productsubid,Productsubname from TVOP2 where Productid='" + ddlProduct.SelectedValue + "'";
        com = new SqlCommand(str, con);
        sqlda = new SqlDataAdapter(com);
        ds = new DataSet();
        sqlda.Fill(ds, "TVOP2");
        ddlProductsub.Items.Clear();
        ddlProductsub.Items.Add("--Select--");
        ddlProductsub.DataValueField = "Productsubid";
        ddlProductsub.DataTextField = "Productsubname";
        ddlProductsub.DataSource = ds;
        ddlProductsub.DataMember = "TVOP2";
        ddlProductsub.DataBind();
        con.Close();
        }
    }
}





Thanks

Hi Johny,

You are trying to bind the Combox and which you set the DataValueField or DataTextField is not available in the source.

You need to check whether the Location_Id is available in the data source.

Already we have given some example source code for similar kind of tasks.

http://www.c-sharpcorner.com/Forums/Thread/169160/dropdowm-did-not-show-the-value-of-next-one.aspx