How to insert record in textbox when select value in dropdown list?

How to insert record in textbox when select value in dropdown list?

Table name(panku)

Id (primary key,int)

Name(nvarchar(max))

Address(nvarchar(max))

Mobile_no(nvarchar(max))

Default2.aspx

<table class="style2" style="background-color: #CCFFFF">

<tr>

<td class="style3">

<p>

Id</p>

</td>

<td>

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

DataTextField="id" DataValueField="id"

onselectedindexchanged="DropDownList1_SelectedIndexChanged" Height="19px"

style="font-style: italic" Width="155px">

</asp:DropDownList>

</td>

</tr>

<tr>

<td class="style3">

<p>

Name</p>

</td>

<td>

<asp:TextBox ID="t1" runat="server" BackColor="Black" ForeColor="#FF6600"

style="font-style: italic"></asp:TextBox>

</td>

</tr>

<tr>

<td class="style3">

<p>

address</p>

</td>

<td>

<asp:TextBox ID="t2" runat="server" BackColor="Black" ForeColor="#FF6600"

style="font-style: italic"></asp:TextBox>

</td>

</tr>

<tr>

<td class="style3">

<p>

Mobile_no</p>

</td>

<td>

<asp:TextBox ID="t3" runat="server" BackColor="Black" ForeColor="#FF6600"

style="font-style: italic"></asp:TextBox>

</td>

</tr>

</table>

</asp:Content>

Default2.aspx

using System;

using System.Collections.Generic;

using System.Linq;

using System.Web;

using System.Web.UI;

using System.Web.UI.WebControls;

using System.Data;

using System.Configuration;

using System.Data.SqlClient;

public partial class Default2 : System.Web.UI.Page

{

    SqlConnection con;

    SqlCommand cmd;

    SqlDataReader dr;

    string id= string.Empty;

    string s = ConfigurationManager.ConnectionStrings["conn"].ToString();

    protected void Page_Load(object sender, EventArgs e)

    {

        if (!Page.IsPostBack)

        {

            FillDropDownList();

        }

    }

    private void FillDropDownList()

    {

        SqlConnection Connection = new SqlConnection(s);

        SqlCommand cmd = new SqlCommand("select [id] from panku", Connection);

        SqlDataAdapter sda = new SqlDataAdapter(cmd);

        DataSet ds = new DataSet();

        sda.Fill(ds);

        DropDownList1.DataSource = ds;

        DropDownList1.DataTextField = "id";

        DropDownList1.DataValueField = "id";

        DropDownList1.DataBind();

        DropDownList1.Items.Insert(0, new ListItem("---Select---", "0"));

    }

    private void FillDropDownList1()

    {

       

    }

    protected void DropDownList1_SelectedIndexChanged1(object sender, EventArgs e)

    {

       

    }

  

    protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)

    {

        id = DropDownList1.SelectedItem.Value;

        SqlConnection Connection = new SqlConnection(s);

        string sqlStatement = string.Empty;

        SqlDataReader dr;

        sqlStatement = "select * from panku where [id]='"+id+"'";

        Connection.Open();

        SqlCommand cmd = new SqlCommand(sqlStatement, Connection);

        cmd.Connection = Connection;

        dr = cmd.ExecuteReader(CommandBehavior.CloseConnection);

        int intRecordCount = 0;

        while (dr.Read())

        {

            intRecordCount = intRecordCount + 1;

            t1.Text = dr.GetString(intRecordCount);

            intRecordCount = intRecordCount + 1;

            t2.Text = dr.GetString(intRecordCount);

            intRecordCount = intRecordCount + 1;

            t3.Text = dr.GetString(intRecordCount);

        }

        dr.NextResult();

    }

   

}

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