Griedview (EDIT ,UPDATE ,DELETE) operations

// First we add namespaces.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data.SqlClient;

public partial class admin_registered : System.Web.UI.Page
{
// create connection
    SqlConnection con = new SqlConnection("Data Source=RAWAT-PC;Initial Catalog=mobile;Integrated Security=True");
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
            show();
        }
    }
    void show()         // function for display data of gridview
    {
        con.Open();
        string s = "select * from customer";
        SqlCommand cmd = new SqlCommand(s, con);
        cmd.ExecuteNonQuery();
        GridView1.DataSource = cmd.ExecuteReader();
        GridView1.DataBind();
        con.Close();
    }
    protected void GridView1_SelectedIndexChanged(object sender, EventArgs e)
    {

    }
    protected void GridView1_PageIndexChanged(object sender, EventArgs e)
    {

    }
    protected void GridView1_PageIndexChanging(object sender, GridViewPageEventArgs e)
    {

    }
    protected void GridView1_RowCancelingEdit(object sender, GridViewCancelEditEventArgs e)
    {

    }
    protected void GridView1_RowEditing(object sender, GridViewEditEventArgs e)
    {
        GridView1.EditIndex = e.NewEditIndex;
    }
    protected void GridView1_RowUpdated(object sender, GridViewUpdatedEventArgs e)
    {

    }

// Code for Update or Edit details with the help of finding the Controls
    protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e)
    {
        TextBox t1 = (TextBox)GridView1.Rows[e.RowIndex].FindControl("textbox1");  \\Finds controls
        TextBox t2 = (TextBox)GridView1.Rows[e.RowIndex].FindControl("textbox2");
        TextBox t3 = (TextBox)GridView1.Rows[e.RowIndex].FindControl("textbox3");
        TextBox t4 = (TextBox)GridView1.Rows[e.RowIndex].FindControl("textbox4");
        TextBox t5 = (TextBox)GridView1.Rows[e.RowIndex].FindControl("textbox5");

        Label lb = (Label)GridView1.Rows[e.RowIndex].FindControl("label3");
        con.Open();
        string s = "update customer set name='" + t1.Text + "',dob='" + t2.Text + "',mob='" + t3.Text + "',username='" + t4.Text + "',password='"+t5.Text+"' where email='" + lb.Text + "'";
        SqlCommand cmd = new SqlCommand(s, con);
        cmd.ExecuteNonQuery();
        GridView1.EditIndex = -1;
        con.Close();
        show();

    }
    protected void GridView1_SelectedIndexChanging(object sender, GridViewSelectEventArgs e)
    {

    }

//Code for delete details or row
    protected void GridView1_RowDeleting(object sender, GridViewDeleteEventArgs e)
    {
        Label lb = (Label)GridView1.Rows[e.RowIndex].FindControl("label3");
        con.Open();
        string s = "delete from customer where email='" + lb.Text + "'";
        SqlCommand cmd = new SqlCommand(s, con);
        cmd.ExecuteNonQuery();
        con.Close();
        show();
    }
}