Related records from one textbox to another

In this blog we will know if we enter some data in first textbox and moves the cursor to second textbox its related records will be shown in second textbox.


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

<!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:Label ID="Label1" runat="server" Text="Id" Width="100px"></asp:Label>
<asp:TextBox ID="TextBox1" runat="server" ontextchanged="TextBox1_TextChanged"
AutoPostBack="True"></asp:TextBox><br />
<asp:Label ID="Label2" runat="server" Text="Name" Width="100px"></asp:Label>
<asp:TextBox ID="TextBox2" runat="server"></asp:TextBox>
</div>
</form>
</body>
</html>



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 Related_records_textboxes
{
public partial class _Default : System.Web.UI.Page
{
string strConnString = ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString;
string str;
SqlCommand com;

protected void TextBox1_TextChanged(object sender, EventArgs e)
{
SqlConnection con = new SqlConnection(strConnString);
con.Open();
str = "select * from employee where id='" + TextBox1.Text + "'";
com = new SqlCommand(str, con);

SqlDataReader reader = com.ExecuteReader();
while (reader.Read())
{
TextBox2.Text = (reader["empname"].ToString());
}
reader.Close();
con.Close();
}
}
}