datalist结合PagedDataSource 类进行分页

  public void sel_callname()
    {

          PagedDataSource ps = new PagedDataSource();//用来给数据控件显示分页的类不能继承
        int curpage = Convert.ToInt32(this.lblCurrentIndex.Text.Trim());
        //获取数据源
        string sqlstr = "select articleid,title,classname,username,dateandtime From db_article";
        com = new SqlCommand(sqlstr, con);
        com.CommandType = CommandType.Text;
        da = new SqlDataAdapter();
        da.SelectCommand = com;
        ds = new DataSet();
        da.Fill(ds);
        ps.DataSource = ds.Tables[0].DefaultView;
        ps.AllowPaging = true;//是否可以分业
        ps.PageSize = 3;//每页显示数据的数量
        ps.CurrentPageIndex = curpage - 1;//取得当前的页码
        this.LinkButton2.Enabled = true;
        this.Linkbutton3.Enabled = true;
        this.Linkbutton4.Enabled = true;
        this.lblCurrentIndex.Enabled = true;
        //如果是当前第一页
        if (curpage == 1)
        {
            this.btnFirst.Enabled = false;//不显示第一页按钮
            this.LinkButton2.Enabled = false;//不显示上一页按钮
        }
        //如果是最后一页
        if (curpage == ps.PageCount)
        {
            this.Linkbutton3.Enabled = false;//不显示下一页按钮
            this.Linkbutton4.Enabled = false;//不显示最后一页按钮
        }
        this.lblPageCount.Text = Convert.ToString(ps.PageCount);//得到最后一页
        for (int i = 1; i <= ps.PageCount; i++)//填充下拉列表值
        {
            DropDownList2.Items.Add("" + i);
        }
        try
        {
            GridView1.DataSource = ps;
            GridView1.DataBind();
        }
        catch (SqlException ex)
        {
            myLabel.Text = "数据库错误！" + ex.Message;
        }
        finally
        {
            ds.Clone();
            com.Clone();
            con.Close();
        }
    }
//怎样获得给DataList中添加一个Bootn按钮进行删除的功能
//首先绑定datalist，str是传进来的任何有效的sql查询语句
    protected void Data_x(string str)
    {
        con = new SqlConnection(ConfigurationSettings.AppSettings["dsn"]);
        da = new SqlDataAdapter(str, con);
        DataSet ds = new DataSet();
        try
        {
            da.Fill(ds, "table");
            DataList1.DataSource = ds;
            DataList1.DataKeyField = "xid";//用来绑定主键这点很重要
            DataList1.DataBind();
        }
        catch (SqlException ex)
        {
            throw (ex);
        }
        finally
        {
            ds.Clone();
            con.Close();
        }
    }
//下面是通过DataList1的ItemCommand事件来获得添加到DataList中的按钮事件
 protected void DataList1_ItemCommand(object source, DataListCommandEventArgs e)
    {
        con = new SqlConnection(System.Configuration.ConfigurationManager.AppSettings["dsn"]);
        //DataList1.DataKeys[e.Item.ItemIndex].ToString();用来获得DataList1.DataKeyField = "xid";//用来绑定主键
        string del_str = "delete from bbs_xinxi where xid=" + DataList1.DataKeys[e.Item.ItemIndex].ToString();
        com = new SqlCommand(del_str, con);
        try
        {
            con.Open();
            if (com.ExecuteNonQuery() > 0)
            {//下面是删除成功后从新绑定DataList
                string _str = "select xid,xuname,xdate,xtext from bbs_xinxi where xjname='" + u_name +
            "'and xyidu=1 order by xdate desc";
                Data_x(_str);
            }
            else
            {
                Page.RegisterStartupScript("key","<script>此信息不能被删除！</script>");
            }
           
        }
        catch (SqlException ex)
        {
            throw (ex);
        }
        finally
        {
            con.Close();
        }
     }