fill grid view details view and datalist view ???with all operations

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

public partial class _Default : System.Web.UI.Page
{
    SqlConnection con = new SqlConnection("Data Source=TOPS17;Initial Catalog=TestGridview;Integrated Security=True");
    SqlConnection cnn = new SqlConnection(ConfigurationManager.AppSettings["cnnstr"].ToString());
    dalUser d1 = new dalUser();
    BAL b1 = new BAL();
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
            fill_data();
            fill_details();
            fill_datalist();
        }

    }
    protected void btn_add_Click(object sender, EventArgs e)
    {
        d1.Name = txtname.Text;
        d1.Password = txtpass.Text;
        b1.insert(d1);
        txtname.Text="";
        txtpass.Text = "";
        txtname.Focus();
        fill_data();
        fill_details();
    }
    public void fill_data()
    {
        DataSet ds = new DataSet();
        ds = b1.fill_grid();
        gridUser.DataSource = ds;
        gridUser.DataBind();
    }

    protected void gridUser_RowEditing(object sender, GridViewEditEventArgs e)
    {
        gridUser.EditIndex = e.NewEditIndex;
        fill_data();
    }
    protected void gridUser_RowUpdating(object sender, GridViewUpdateEventArgs e)
    {
        int id = int.Parse(gridUser.DataKeys[e.RowIndex].Value.ToString());
        TextBox txtname = (TextBox)gridUser.Rows[e.RowIndex].FindControl("txtname");
        TextBox txtpass = (TextBox)gridUser.Rows[e.RowIndex].FindControl("txtpass");
        d1.Name=txtname.Text;
        d1.Password = txtpass.Text;
        b1.Updateuser(id,d1);
        gridUser.EditIndex = -1;
        fill_data();

    }
    protected void gridUser_RowDeleting(object sender, GridViewDeleteEventArgs e)
    {
        int id = int.Parse(gridUser.DataKeys[e.RowIndex].Value.ToString());
        b1.deleteuser(id);
        fill_data();
    }
    protected void gridUser_RowCancelingEdit(object sender, GridViewCancelEditEventArgs e)
    {
        gridUser.EditIndex = -1;
        fill_data();
    }
    protected void gridUser_SelectedIndexChanged(object sender, EventArgs e)
    {

    }
    protected void DetailsView1_ModeChanging(object sender, DetailsViewModeEventArgs e)
    {
        DetailsView1.ChangeMode(e.NewMode);
        fill_details();
    }
    public void fill_details()
    {
        DataSet ds = new DataSet();
        ds = b1.fill_detailsview();
        DetailsView1.DataSource = ds;
        DetailsView1.DataBind();
    }
    protected void gridUser_PageIndexChanging(object sender, GridViewPageEventArgs e)
    {
        gridUser.PageIndex = e.NewPageIndex;
        fill_data();
    }
    protected void DetailsView1_PageIndexChanging(object sender, DetailsViewPageEventArgs e)
    {
        DetailsView1.PageIndex = e.NewPageIndex;
        fill_details();
    }
    protected void gridUser_Sorting(object sender, GridViewSortEventArgs e)
    {
      
    }
    protected void DetailsView1_ItemUpdating(object sender, DetailsViewUpdateEventArgs e)
    {

    }
    protected void DetailsView1_ItemDeleting(object sender, DetailsViewDeleteEventArgs e)
    {
        Label l = (Label)DetailsView1.FindControl("Label3");
        int id123 = int.Parse(l.Text.ToString());
        b1.deleteuser_details(id123);
        fill_details();
    }
    protected void DetailsView1_ItemInserting(object sender, DetailsViewInsertEventArgs e)
    {

        TextBox tu = (TextBox)DetailsView1.FindControl("TextBox2");
        TextBox tp = (TextBox)DetailsView1.FindControl("TextBox4");
       
      
    }
    public void fill_datalist()
    {
        SqlDataAdapter da = new SqlDataAdapter("select * from tbl_reg", cnn);
        DataSet ds = new DataSet();
        da.Fill(ds);
        DataList1.DataSource = ds;
        DataList1.DataBind();

    }
    protected void insert_Click(object sender, EventArgs e)
    {
        TextBox txtu = (TextBox)gridUser.HeaderRow.FindControl("TextBox7");
        TextBox txtp = (TextBox)gridUser.HeaderRow.FindControl("TextBox8");
        d1.Name = txtu.Text;
        d1.Password = txtp.Text;
        b1.insert(d1);
        txtu.Text = "";
        txtp.Text = "";
        txtu.Focus();
        fill_data();
        fill_details();
    }
    protected void DataList1_DeleteCommand(object source, DataListCommandEventArgs e)
    {

    }
    protected void DataList1_EditCommand(object source, DataListCommandEventArgs e)
    {
        DataList1.EditItemIndex = e.Item.ItemIndex;
        fill_datalist();
    }
    protected void DataList1_UpdateCommand(object source, DataListCommandEventArgs e)
    {
        Label lid = (Label)e.Item.FindControl("lblid");
        int id1 = int.Parse(lid.Text.ToString());
        TextBox txtu = (TextBox)e.Item.FindControl("txtuser");
        TextBox txtp = (TextBox)e.Item.FindControl("txtpass");
        SqlCommand cmd = new SqlCommand("update tbl_reg set username='"+txtu.Text+"',password='"+txtp.Text+"' where id='"+id1+"'",con);
        con.Open();
        cmd.ExecuteNonQuery();
        con.Close();
        DataList1.EditItemIndex = -1;
        fill_datalist();
   
    }
    protected void DataList1_CancelCommand(object source, DataListCommandEventArgs e)
    {
        DataList1.EditItemIndex = -1;
        fill_datalist();
    }
}