code for updating the table in ASP.Net using c#

Ajith,

Please mark answer as accepted answer if it resolves your problem.

Simple Create a Button and put the click event on it and write below code in that event which
is in the .cs file

protected void upd_Click(object sender, EventArgs e)
    {
        SqlConnection cn = new SqlConnection(@"Put the Connection String");
        cn.Open();
        SqlCommand cmd = new SqlCommand("UPDATE Cust_master SET Name ='" +         TextBox2.Text.Trim() + "', Contact ='" + TextBox3.Text.Trim() + "', Address ='" +         TextBox4.Text.Trim() + "'WHERE Cust_id =" + TextBox1.Text.Trim() + "", cn);
        cmd.ExecuteNonQuery();
        cn.Close();
        load();
    }

also code file is atteched here