请问这个数据库连接怎么调试？
using   System;
using   System.Data;
using   System.Configuration;
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   _Default   :   System.Web.UI.Page  
{
        protected   void   Page_Load(object   sender,   EventArgs   e)
        {
                string   strConn= "server=(local);database=Northwind;uid   =sa;   Pwd=123456 ";

                SqlConnection   cn=new   SqlConnection(strConn);
                cn.Open;
                SqlCommand   cm=new   SqlCommand( "select   *   from   categories ",cn);
                SqlDataReader   dr=cm.ExecuteReader();
                dgCust.DataSource=dr;
                dgCust.DataBind();
                cn.Close;


        }
}


调试结果为：


Server   Error   in   '/WebSite2 '   Application.
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Compilation   Error  
Description:   An   error   occurred   during   the   compilation   of   a   resource   required   to   service   this   request.   Please   review   the   following   specific   error   details   and   modify   your   source   code   appropriately.  

Compiler   Error   Message:   CS0201:   Only   assignment,   call,   increment,   decrement,   and   new   object   expressions   can   be   used   as   a   statement

Source   Error:
 

Line   17:  
Line   18:                   SqlConnection   cn=new   SqlConnection(strConn);
Line   19:                   cn.Open;
Line   20:                   SqlCommand   cm=new   SqlCommand( "select   *   from   categories ",cn);
Line   21:                   SqlDataReader   dr=cm.ExecuteReader();
 

Source   File:   d:\Documents   and   Settings\Administrator\My   Documents\Visual   Studio   2005\WebSites\WebSite2\Default.aspx.cs         Line:   19  

--------------------------------------------
Version   Information:   Microsoft   .NET   Framework   Version:2.0.50727.42;   ASP.NET   Version:2.0.50727.210  



------解决方案--------------------
少了括号，改成这样
public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)