protected void Button2_Click(object sender, EventArgs e)
{
string Delstring=DataList1.DataKeys[e.Item.ItemIndex];
OleDbConnection conn = new OleDbConnection();
conn.ConnectionString = "provider=Microsoft.Jet.OLEDB.4.0;data source=E:\\asp.net开发\\ASP.NET完全自学手册(光盘)\\源文件\\ch10\\App_Data\\MsgBoard.mdb";
string sql = "delete post where postid='" + Delstring + "'";
OleDbCommand comm = new OleDbCommand(sql, conn);
conn.Open();
comm.ExecuteNonQuery();
conn.Close();
Response.Redirect("index.aspx");

}

编译器错误信息: CS0117: “System.EventArgs”并不包含“Item”的定义

private void InitializeComponent()
{
this.DataList1.ItemCommand += new System.Web.UI.WebControls.DataListCommandEventHandler(this.DataList1_ItemCommand);
this.DataList1.ItemDataBound += new System.Web.UI.WebControls.DataListItemEventHandler(this.DataList1_ItemDataBound);
}
#endregion
protected void DataList1_ItemDataBound(object source, DataListItemEventArgs e)
{
Button Button2 = (Button)e.Item.FindControl("button2");
if (Button2 != null)
{
Button2.Attributes.Add("onclick", "return confirm('你确定要删除所选的内容吗？');");
}
}
protected void DataList1_ItemCommand(object source, DataListCommandEventArgs e)
{
if (e.CommandName.ToLower() == "delete")
{
OleDbConnection conn = new OleDbConnection();
conn.ConnectionString = "provider=Microsoft.Jet.OLEDB.4.0;data source=E:\\asp.net开发\\ASP.NET完全自学手册(光盘)\\源文件\\ch10\\App_Data\\MsgBoard.mdb";
string sID = DataList1.DataKeys[e.Item.ItemIndex].ToString();//获取id
string sql = "delete from post where postid=" + sID;
OleDbCommand comm = new OleDbCommand(sql, conn);
conn.Open();
comm.ExecuteNonQuery();
conn.Close();
Response.Redirect("index.aspx");
}
}

这样实现我想要的功能了。谢谢大家