命名空间“System.Data”中不存在类型或命名空间名称“SqlConnection”(是缺少程序集引用吗?)
编译器错误信息: CS0234: 命名空间“System.Data”中不存在类型或命名空间名称“SqlConnection”(是缺少程序集引用吗?)

源错误:

 

行 12: using System.Web.UI.HtmlControls;
行 13: using System.Data.SqlClient;
行 14: using System.Data.SqlConnection;



 我是用c#asp.net2005 sql数据库.以下是我的using:
using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Web;
using System.Web.Mobile;
using System.Web.SessionState;
using System.Web.UI;
using System.Web.UI.MobileControls;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;
using System.Data.SqlClient;
using System.Data.SqlConnection;
using System.Data.OracleClient;
using System.Web.Page;
using System.Web.Services;
using System.Diagnostics;
using System.Configuration;
using System.Web.Security;

using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;


------解决方案--------------------
using System.Data;
using System.Data.SqlClient;
这两句就行了。