关于datatable的有关问题，

       
        DBaction db = new DBaction();
        string sql1 = "select * from adlist where ad_top ='Y'";
        string sql2 = "select * from adlist where ad_top ='N'";
        DataTable dt1 = db.Select(sql1);
        DataTable dt2 = db.Select(sql2);
        DataTable dt = new DataTable();
        dt = dt2;
        dt.Merge(dt1);//将dt2接入dt1变成dt。
        DataSet ds = new DataSet();
        ds.Tables.Add(dt);

        sqlDataAdapter sda = new OleDbDataAdapter("select * from t_product",conn);//省略了连接过程代码       
        DataSet ds = new DataSet();        
        sda.Fill(ds, pager1.PageSize * (pager1.CurrentPageIndex - 1), pager1.PageSize, "temptbl");
        DataList1.DataSource = ds.Tables["temptbl"];
        DataList1.DataBind();

protected void DataBinds()
    {
        SqlConnection cn = new SqlConnection("Data Source=.;Initial Catalog=Test;Integrated Security=True");//连接并实例化数据库
        string sql = "select * from Student";//定义查询语句
        SqlDataAdapter da = new SqlDataAdapter(sql, cn);//实例化对象Adapter
        DataSet ds = new DataSet();//实例化DataSet
        da.Fill(ds, "Student");//填充

        PagedDataSource pds = new PagedDataSource();//初始化分页事例
        pds.DataSource = ds.Tables["Student"].DefaultView;
        pds.AllowPaging = true;//启动分页
        pds.PageSize = 5;//每页显示的个数


        CurrentIndex = int.Parse(this.Label1.Text) - 1;//获取当前页数索引
        pds.CurrentPageIndex = CurrentIndex;
        if (CurrentIndex == 0)
        {//如果是第一页，上一页和第一页的控件不可点击
            this.PreviousLB.Enabled = false;
            this.FirstLB.Enabled = false;
            this.NextLB.Enabled = true;
            this.EndLB.Enabled = true;
        }
        else if (CurrentIndex == pds.PageCount - 1)
        {
            //如果是最后一页，下一页和最后一页空间不可点击
            this.PreviousLB.Enabled = true;
            this.FirstLB.Enabled = true;
            this.NextLB.Enabled = false;
            this.EndLB.Enabled = false;

        }
        else
        {
            this.PreviousLB.Enabled = true;
            this.FirstLB.Enabled = true;
            this.NextLB.Enabled = true;
            this.EndLB.Enabled = true;

        }
        this.Label2.Text = pds.PageCount.ToString();//获取总页数
        DataList1.DataSource = pds;//绑定DataList数据
        DataList1.DataBind();
    }
    protected void FirstLB_Click(object sender, EventArgs e)//首页
    {
        this.Label1.Text = "1";//页数为1
        DataBinds();
    }
    protected void PreviousLB_Click(object sender, EventArgs e)
    {
        this.Label1.Text = (int.Parse(Label1.Text) - 1).ToString();//页数减1
        DataBinds();
    }
    protected void NextLB_Click(object sender, EventArgs e)//下一页
    {
        this.Label1.Text = (int.Parse(this.Label1.Text) + 1).ToString();//页数加1
        DataBinds();

    }
    protected void EndLB_Click(object sender, EventArgs e)//末页
    {
        this.Label1.Text = Label2.Text;//页数为最后一页
        DataBinds();
    }
    protected void JumpLB_Click(object sender, EventArgs e)
    {

        try
        {

            if (int.Parse(TextBox1.Text) > 0 && int.Parse(TextBox1.Text) <= int.Parse(Label2.Text))
            {
                this.Label1.Text = TextBox1.Text;
                DataBinds();
            }
            else
            {
                Response.Write("<script>alert('请输入有效数字')</script>");
                TextBox1.Text = null;
            }
        }
        catch
        {
            Response.Write("<script>alert('系统出错')</script>");
            Response.Redirect("~/Default.aspx");
        }
    }