In this blog we will know when we select any item from the dropdownlist its related values will be displayed in the other webpage.

test1.aspx

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="test1.aspx.cs" Inherits="Dropdownlist_querystring.test1" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" >

<head runat="server">

<title>Untitled Page</title>

</head>

<body>

<form id="form1" runat="server">

<div>

<asp:DropDownList ID="DropDownList1" runat="server"

onselectedindexchanged="DropDownList1_SelectedIndexChanged">

</asp:DropDownList>

</div>

</form>

</body>

</html>

test1.aspx.cs

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 Dropdownlist_querystring

{

public partial class test1 : System.Web.UI.Page

{

string strConnString = ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString;

string str;

SqlCommand com;

protected void Page_Load(object sender, EventArgs e)

{

if (!IsPostBack)

{

binddrop();

}

}

private void binddrop()

{

DropDownList1.AutoPostBack = true;

SqlConnection con = new SqlConnection(strConnString);

if (!IsPostBack)

{

DropDownList1.Items.Add("Choose empid");

con.Open();

str = "select * from employee";

com = new SqlCommand(str, con);

SqlDataReader reader = com.ExecuteReader();

while (reader.Read())

{

DropDownList1.Items.Add(reader["empid"].ToString());

}

reader.Close();

con.Close();

}

}

protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)

{

Response.Redirect("test2.aspx?empid=" + DropDownList1.SelectedItem.Text + "");

}

}

}

test2.aspx

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="test2.aspx.cs" Inherits="Dropdownlist_querystring.test2" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" >

<head runat="server">

<title>Untitled Page</title>

</head>

<body>

<form id="form1" runat="server">

<div>

<table border="1" style="border-collapse: collapse" cellspacing="1">

<tr>

<td width="77" height="16" align="left" ><b><font size="2" color="red">Empname:</font></b></td>

<td width="77" height="16" align="left" ><b><font size="2"> <asp:Label ID="Label1" runat="server" Font-Bold="True"></asp:Label><br /></font></b></td>

</tr>

<tr>

<td width="77" height="16" align="left" ><b><font size="2" color="red">Empaddress:</font></b></td>

<td width="77" height="16" align="left" ><b><font size="2"> <asp:Label ID="Label2" runat="server" Font-Bold="True"></asp:Label><br /></font></b></td>

</tr>

<tr>

<td width="77" height="16" align="left" ><b><font size="2" color="red">Empsal:</font></b></td>

<td width="77" height="16" align="left" ><b><font size="2"> <asp:Label ID="Label3" runat="server" Font-Bold="True"></asp:Label><br /></font></b></td>

</tr>

<tr>

<td width="77" height="16" align="left" ><b><font size="2" color="red">Empphone:</font></b></td>

<td width="77" height="16" align="left" ><b><font size="2"> <asp:Label ID="Label4" runat="server" Font-Bold="True"></asp:Label><br /></font></b></td>

</tr>

<tr>

<td width="77" height="16" align="left" ><b><font size="2" color="red">Empfax:</font></b></td>

<td width="77" height="16" align="left" ><b><font size="2"> <asp:Label ID="Label5" runat="server" Font-Bold="True"></asp:Label><br /></font></b></td>

</tr>

<tr>

<td width="77" height="16" align="left" ><b><font size="2" color="red">Empcity:</font></b></td>

<td width="77" height="16" align="left" ><b><font size="2"> <asp:Label ID="Label6" runat="server" Font-Bold="True"></asp:Label><br /></font></b></td>

</tr>

<tr>

<td width="77" height="16" align="left" ><b><font size="2" color="red">Empstate:</font></b></td>

<td width="77" height="16" align="left" ><b><font size="2"> <asp:Label ID="Label7" runat="server" Font-Bold="True"></asp:Label><br /></font></b></td>

</tr>

<tr>

<td width="77" height="16" align="left" ><b><font size="2" color="red">Empzip:</font></b></td>

<td width="77" height="16" align="left" ><b><font size="2"> <asp:Label ID="Label8" runat="server" Font-Bold="True"></asp:Label><br /></font></b></td>

</tr>

<tr>

<td width="77" height="16" align="left" ><b><font size="2" color="red">Emplic:</font></b></td>

<td width="77" height="16" align="left" ><b><font size="2"> <asp:Label ID="Label9" runat="server" Font-Bold="True"></asp:Label><br /></font></b></td>

</tr>

<tr>

<td width="77" height="16" align="left" ><b><font size="2" color="red">Empstatus:</font></b></td>

<td width="77" height="16" align="left" ><b><font size="2"> <asp:Label ID="Label10" runat="server" Font-Bold="True"></asp:Label><br /></font></b></td>

</tr>

</table>

</div>

</form>

</body>

</html>

test2.aspx.cs

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 Dropdownlist_querystring

{

public partial class test2 : System.Web.UI.Page

{

string strConnString = ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString;

string str;

string s1;

SqlCommand com;

protected void Page_Load(object sender, EventArgs e)

{

try

{

SqlConnection con = new SqlConnection(strConnString);

con.Open();

s1 = Request.QueryString[0];

str = "select * from employee where empid='" + s1 + "'";

com = new SqlCommand(str, con);

SqlDataReader reader;

reader = com.ExecuteReader();

if (reader.Read())

{

Label1.Text = reader["empname"].ToString();

Label2.Text = reader["empaddress"].ToString();

Label3.Text = reader["empsal"].ToString();

Label4.Text = reader["empphone"].ToString();

Label5.Text = reader["empfax"].ToString();

Label6.Text = reader["empcity"].ToString();

Label7.Text = reader["empstate"].ToString();

Label8.Text = reader["empzip"].ToString();

Label9.Text = reader["emplic"].ToString();

Label10.Text = reader["empstatus"].ToString();

}

}

catch (Exception ex)

{

Response.Write(ex.Message);

}

}

}

}