protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e)
{
int index = GridView1.EditIndex;
GridViewRow row = GridView1.Rows[index];
TextBox t1 = row.FindControl("txtemp_name") as TextBox;
TextBox t2 = row.FindControl("txtemp_add") as TextBox;
TextBox t3 = row.FindControl("txtemp_mob") as TextBox;
TextBox t4 = row.FindControl("txtsalary") as TextBox;
string t5= GridView1.DataKeys[e.RowIndex].Value.ToString();
string dt = "update employee set emp_name='" + t1.Text + "',emp_add='" + t2.Text + "',emp_mob='" + t3.Text+ "',salary='" + t4.Text+ "'where emp_id=" + t5+ "";
con.Open();
cmd = new SqlCommand(dt, con);
cmd.ExecuteNonQuery();
GridView1.EditIndex = -1;
con.Close();
bind();
Button b1=row.FindControl("yourbuttonname") as Button;
b1.Text="Off";
}