Create A WebService Coding for Cascading DropdownList 1 to Dropdown List 2

Hi Aditya,


Try this...



Create table TVOP1(Productid varchar(50),Productname varchar(50))


Create table TVOP2(Productsubid varchar(50),Productsubname varchar(50),Productid varchar(50))



<%@ 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
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