ASP.NET中GridView批量删除

前台：
<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" Width="100%" DataKeyNames="news_id" Css AllowPaging="True"   PageSize="5" >
              
                 <Columns>
                     <asp:TemplateField>
                         <ItemTemplate>
                             &nbsp;<asp:CheckBox ID="cbSelect" runat="server" />
                         </ItemTemplate>
                         <ItemStyle HorizontalAlign="Center" Width="30px" />
                     </asp:TemplateField>
                     <asp:BoundField DataField="news_title" HeaderText="最新动态标题">
                         <ItemStyle HorizontalAlign="Center" Width="200px" />
                     </asp:BoundField>
                     <asp:BoundField DataField="news_body" HeaderText="最新动态内容" >
                         <ItemStyle HorizontalAlign="Center" />
                     </asp:BoundField>
                     <asp:BoundField DataField="news_id" Visible="False" />
                 </Columns>
                   <PagerStyle HorizontalAlign="Center" />
             </asp:GridView>
                 </td>
             </tr>
             <tr>
                 <td valign="top">
                 <asp:CheckBox ID="cbAll" runat="server" Text="全选" AutoPostBack="True" OnCheckedChanged="CheckAll" Css />
                 <asp:Button ID="btnDelete" runat="server" Text="删除所选" OnClick="btnDelete_Click" Css /></td>
             </tr>

后台：

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;
using System.Data.SqlClient;
public partial class admin_admin_news : System.Web.UI.Page
{
     protected void Page_Load(object sender, EventArgs e)
     {
         if (!Page.IsPostBack)
         {
             btnDelete.Attributes.Add("onclick", "return confirm('您真的要删除该行数据吗？');");
             BindView();
         }
     }
     protected void CheckAll(object sender, EventArgs e)
     {
         CheckBox cbAll = (CheckBox)sender;
         if (cbAll.Text == "全选")
         {
             foreach (System.Web.UI.WebControls.GridViewRow gr in this.GridView1.Rows)
             {
                 CheckBox chk = (CheckBox)gr.FindControl("cbSelect");
                 chk.Checked = cbAll.Checked;
             }
         }
     }
     public void BindView()
     {
         SqlConnection con = Data.BuilderCon();
         String Sel = "select * from news order by news_id desc";
         DataSet ds = Data.BuilderSet(Sel);
         this.GridView1.DataSource = ds;
         this.GridView1.DataBind();
     }
     protected void btnDelete_Click(object sender, EventArgs e)
     {
         foreach (GridViewRow dgi in this.GridView1.Rows)
         {
             CheckBox cb = (CheckBox)dgi.FindControl("cbSelect");
             if (cb.Checked)
             {
                 Int32 index = dgi.RowIndex;
                 DataKey key = this.GridView1.DataKeys[index];
                 String newsid = key.Values["news_id"].ToString();
                 //以下执行删除操作
                 String strSql = "delete news where news_id = '" + newsid + "'";
                 SqlCommand com = Data.BuilderCom(strSql);
                 Int32 num = com.ExecuteNonQuery();
                 if (num > 0)
                 {
                     Response.Write("<script>alert('成功删除所选！');</script>");
                 }
                 cbAll.Checked = false;
             }
         }
         this.GridView1.PageIndex = 0;
         BindView();
     }
}