C#

The best overloaded method match for 'System.Data.SqlClient.SqlDataAdapter.SqlDataAdapter(string, System.Data.SqlClient.SqlConnection)

<pre lang="c#">Argument 2: cannot convert from 'System.Data.SqlServerCe.SqlCeConnection' to 'System.Data.SqlClient.SqlConnection'

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace Game
{
    public partial class Form1 : Form
    {
        public OpenFileDialog dialog = new OpenFileDialog();
        System.Data.SqlServerCe.SqlCeConnection con;
        System.Data.SqlServerCe.SqlCeDataAdapter da1;
        DataSet ds1;



        public Form1()
        {
            InitializeComponent();
        }

        private void btn_sel_Click(object sender, EventArgs e)
        {
            
            //dialog.Filter = "*.sdf";
            dialog.ShowDialog();
            MessageBox.Show(dialog.FileName);
            loadconnection();

        }

        private void btn_close_Click(object sender, EventArgs e)
        {
            Application.Exit();
        }

        public void loadconnection()
        {
            con = new System.Data.SqlServerCe.SqlCeConnection();
            con.ConnectionString = "Data Source=" + dialog.FileName + ""; //opening dialog (selected file)

            con.Open();


            ds1 = new DataSet();
            string sql = "SELECT * From tbl_games";
            da1 = new System.Data.SqlClient.SqlDataAdapter(sql, con);
            da1.Fill(ds1, "Name");

            con.Close();
        }

    }
}

if (txtdisc.Text ==null)
           {

               txttot22013 = txtpr22013 + txtpr22014 + txtpr22015 + txtpr22016 + txtpr22017;

               Double txtdisc22013 = Convert.ToDouble(txtdisc.Text);

               txttot22013 = txttot22013 - txtdisc22013;

               txttot.Text = txttot22013.ToString();
           }

           else
           {
               txttot22013 = txtpr22013 + txtpr22014 + txtpr22015 + txtpr22016 + txtpr22017;

               txttot.Text = txttot22013.ToString();
           }

           if (txtvat.Text == null)
           {
               MessageBox.Show("Enter Vat Amount");
           }

           else
           {
               Double txtvat22013 = Convert.ToDouble(txtvat.Text);

               txtvat22013 = txtvat22013 / 100;

               txtvat22013 = txtvat22013 * txttot22013;

               Double txtvatinclu22013 = txtvat22013 + txttot22013;

               txtvatinclu.Text = txtvatinclu22013.ToString();
           }