ขอ code insert update delete ของ C#.net หน่อยคาบบ ขอบคุนคาบผม

using System;
using System.Collections.Generic;
using System.Data.SqlClient;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data.OleDb;
using System.Data;

public partial class _Default : System.Web.UI.Page 
{
    protected void Page_Load(object sender, EventArgs e)
    {
        string connectionString = "server=.;" + "initial catalog = test_again;" + "user id=koravit;" + "password=koravit";

        SqlConnection sqlConn = new SqlConnection(connectionString);
        SqlCommand sqlComm = new SqlCommand();
        sqlComm = sqlConn.CreateCommand();
        sqlComm.CommandText = @"INSERT INTO section (s_id) VALUES (@s_id)";
        sqlComm.Parameters.Add("@s_id", SqlDbType.VarChar);
        sqlComm.Parameters["@s_id"].Value = TextBox1.Text;
        sqlConn.Open();
        sqlComm.ExecuteNonQuery();
        sqlConn.Close();
    }

}