“System.Web.UI.Control”并不包含“Checked”的定义?
各位大哥帮我看一下这个错误怎么解？

我是想点击delete（button控件)的候，把datalist1里的checkbox.checked为true的记录都删掉。

编译器错误信息: CS0117: “System.Web.UI.Control”并不包含“Checked”的定义

行 40: foreach(DataListItem ChlItem in DataList1.Items)
行 41: {
行 42: bool IsCheck=(CheckBox)(ChlItem.FindControl( "DeleteOrNot ")).Checked; //此行红色，难道这一行有错？
行 43:
行 44: if (IsCheck)

.cs部分代码

using System;
using System.Data;
using System.Data.SqlClient;
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 checkbox_delete : System.Web.UI.Page
{
SqlConnection conn = new SqlConnection( "Data Source=.;Initial Catalog=9957_PRODUCT_SMS;Integrated Security=True ");
protected void Page_Load(object sender, EventArgs e)
{


if (!IsPostBack)
{
bindtosource();
}
}

protected void bindtosource()
{

SqlCommand comm = new SqlCommand( "select 身份证号码,学生姓名 from 学生 ", conn);
conn.Open();
SqlDataReader dr = comm.ExecuteReader();
DataList1.DataSource = dr;
DataList1.DataBind();
conn.Close();

}
protected void delete_Click(object sender, EventArgs e)
{

foreach(DataListItem ChlItem in DataList1.Items)
{
bool IsCheck=(CheckBox)(ChlItem.FindControl( "DeleteOrNot ")).Checked;

if (IsCheck)

{
String commstr = "delete 学生 where 身份证号码= ' " + DataList1.DataKeys[ChlItem.ItemIndex] + " ' ";
SqlCommand comm_del = new SqlCommand(commstr, conn);
conn.Open();
try
{
comm_del.ExecuteNonQuery();
}
catch (SqlException ex) { Response.Write(ex.Message); }
conn.Close();
bindtosource();

}

}

}

}






[解决办法]
bool IsCheck=(CheckBox)(ChlItem.FindControl( "DeleteOrNot ")).Checked;==> bool IsCheck=((CheckBox)ChlItem.FindControl( "DeleteOrNot ")).Checked;