PostgreSQL , C#, .NET

hello,

    i'm just about to start C#.net using PostgreSQL as my database... i used Npgsql as my connector.. i can access my dbase using it and i can display the data to grid. but i need help for inserting into dbase. here's my code:


using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using Npgsql;//  <-- must be added through reference then browse the .dll, inorder to use connection,command,reader etc.
using System.Windows.Forms; //   <-- also added reference under .NET tab then "System.Windows.Forms", inorder to use msgbox
public partial class _Default : System.Web.UI.Page
{
 
    protected void Button1_Click(object sender, EventArgs e)
    {
        string DefCon = "server=localhost;database=testing;uid=postgres;pwd=argets";
       
        NpgsqlConnection MyConnection = new NpgsqlConnection(DefCon);
        string STRsql = " SELECT * FROM nametable where last ='" + TextBox1.Text + "' and first like '" + TextBox2.Text + "'";
        NpgsqlCommand MyCommand = MyConnection.CreateCommand();
        MyCommand.CommandText = STRsql;
       
        NpgsqlDataAdapter myDataAdapter = new NpgsqlDataAdapter();
        myDataAdapter.SelectCommand = MyCommand;
        DataSet myDataSet = new DataSet();
        MyConnection.Open();
        int recexist = myDataAdapter.Fill(myDataSet);
        if (recexist == 0)
        {
            MessageBox.Show("invalid username");
            Response.Redirect("Default.aspx?Login=Invalid");
        }
        else
        {
            MessageBox.Show("welcome");
            Response.Redirect("Default.aspx");

        }

        MyConnection.Close();
    }
    protected void Page_Load(object sender, EventArgs e)
    {
        //**********************************
        // hard coded to connect datagrid  *
        //**********************************
        string DefCon = "server=localhost;database=testing;uid=postgres;pwd=argets";
       
        NpgsqlConnection MyConnection = new NpgsqlConnection(DefCon);
        string tmpSQL = "select * from nametable order by last asc";
        NpgsqlCommand rsCommand = MyConnection.CreateCommand();
        rsCommand.CommandText = tmpSQL;

        NpgsqlDataAdapter rsDATAadapter = new NpgsqlDataAdapter();
        rsDATAadapter.SelectCommand = rsCommand;
        DataSet myDataSet = new DataSet();

        MyConnection.Open();
        rsDATAadapter.Fill(myDataSet);
        GridView1.DataSource = myDataSet;
        GridView1.DataBind();
    }

    protected void bttnSave_Click(object sender, EventArgs e)
    {
        string DefCon = "server=localhost;database=testing;uid=postgres;pwd=argets";
        NpgsqlConnection MyCon = new NpgsqlConnection(DefCon);
        string Temp = "INSERT INTO nametable(last,first) VALUES('" + txtlast.Text + "','" + txtfirst.Text + "')";
        NpgsqlCommand RsBem = MyCon.CreateCommand();
        RsBem.CommandText = Temp;

        NpgsqlDataAdapter RsDT = new NpgsqlDataAdapter();
        RsDT.SelectCommand = RsBem;
        MyCon.Open();
        Response.Redirect("Default.aspx");
    }
}

Please help me on bttnSave click. PM me if you reply to this topic..