批量删除

<%# DataBinder.Eval(Container.DataItem,"id") %><%# DataBinder.Eval(Container.DataItem,"mm") %><%# DataBinder.Eval(Container.DataItem,"id") %><%# DataBinder.Eval(Container.DataItem,"mm") %><%# DataBinder.Eval(Container.DataItem,"id") %><%# DataBinder.Eval(Container.DataItem,"mm") %><%# DataBinder.Eval(Container.DataItem,"id") %><%# DataBinder.Eval(Container.DataItem,"mm") %><%# DataBinder.Eval(Container.DataItem,"id") %><%# DataBinder.Eval(Container.DataItem,"mm") %><%# DataBinder.Eval(Container.DataItem,"id") %><%# DataBinder.Eval(Container.DataItem,"mm") %><%# DataBinder.Eval(Container.DataItem,"id") %><%# DataBinder.Eval(Container.DataItem,"mm") %><asp:DataList id="DataList2" style="Z-INDEX: 101; LEFT: 280px; POSITION: absolute; TOP: 104px"
  runat="server">
  <ItemTemplate>
  <asp:CheckBox id="chb" runat="server"></asp:CheckBox><%# DataBinder.Eval(Container.DataItem,"id") %>
  <%# DataBinder.Eval(Container.DataItem,"mm") %>
  </ItemTemplate>
  </asp:DataList>
  <asp:Button id="Button1" style="Z-INDEX: 102; LEFT: 280px; POSITION: absolute; TOP: 64px" runat="server"
  Text="全选"></asp:Button>
  <asp:Button id="Button2" style="Z-INDEX: 103; LEFT: 336px; POSITION: absolute; TOP: 64px" runat="server"
  Text="delete"></asp:Button>


public void data()
  {
  SqlConnection con=new SqlConnection("server=.;database=pubs;uid=sa;pwd=123");
   SqlDataAdapter sda=new SqlDataAdapter("select * from ta",con);
   DataSet ds=new DataSet();
   sda.Fill(ds,"jobs");
   this.DataList2.DataSource=ds;
   this.DataList2.DataKeyField="id";
   this.DataList2.DataBind();
  }

  private void Button1_Click(object sender, System.EventArgs e)
  {
   foreach(System.Web.UI.WebControls.DataListItem Item in this.DataList2.Items)
   {
    CheckBox chb=(CheckBox)Item.FindControl("chb");
    chb.Checked=true;
   }
  }

  private void Button2_Click(object sender, System.EventArgs e)
  {
    foreach(System.Web.UI.WebControls.DataListItem Item in this.DataList2.Items)
       {
          CheckBox chb=(CheckBox)Item.FindControl("chb");
     if(chb.Checked==true)
     {
       string id=this.DataList2.DataKeys[Item.ItemIndex].ToString();
      SqlConnection con=new SqlConnection("server=.;database=pubs;uid=sa;pwd=123");
      con.Open();
      SqlCommand cmd=new SqlCommand("delete from ta where id='"+id+"'",con);
      cmd.ExecuteNonQuery();
      

     }
   }
   data();
    
     

  }