DataView控件绑定错误

前台代码：

                    <asp:GridView ID="GridView1" runat="server" Width="600px" AutoGenerateColumns="False" CellPadding="2" DataKeyNames="wyx_id" EnableViewState="False" AllowPaging="True" OnSelectedIndexChanged="GridView1_SelectedIndexChanged" DataSourceID="AccessDataSource1">
                        <Columns>
                            <asp:BoundField DataField="wyx_id" HeaderText="序号" />
                            <asp:BoundField HeaderText="分类" />
                            <asp:TemplateField HeaderText="标题">
                                <ItemTemplate>
                                    <asp:HyperLink ID="HyperLink1" runat="server" Text='<%# Eval("wyx_title") %>' NavigateUrl='<%# "admin_edit.aspx?id="+Eval("id") %>'></asp:HyperLink>&nbsp;
                                </ItemTemplate>
                            </asp:TemplateField>
                            <asp:BoundField DataField="wyx_date" HeaderText="日期" />
                            <asp:CommandField ShowEditButton="True" />
                            <asp:CommandField ShowDeleteButton="True" />
                            <asp:CommandField ShowSelectButton="True" />
                        </Columns>
                        <PagerSettings FirstPageText="首页" LastPageText="尾页" Mode="NextPreviousFirstLast"
                            NextPageText="下一页" PreviousPageText="上一页" />
                    </asp:GridView>
                    <asp:AccessDataSource ID="AccessDataSource1" runat="server" DataFile="~/data/wyx.mdb"
                        SelectCommand="SELECT [wyx_id], [wyx_class], [wyx_title], [wyx_date] FROM [wyx_text]">
                    </asp:AccessDataSource>




后台代码：

using System;
using System.Data;
using System.Configuration;
using System.Collections;
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;


public partial class admin_admin_text : System.Web.UI.Page
{

    protected void Page_Load(object sender, EventArgs e)
    {

    }

    protected void GridView1_SelectedIndexChanged(object sender, EventArgs e)
    {
        DataSet ds = Socut.Data.ExecuteDataSet("SELECT * FROM wyx_text ORDER BY wyx_id DESC");//实例化DataSet
        GridView1.DataSource = ds;  //设置数据源
        GridView1.DataBind();       //绑定数据
                        
    }


}