aspx最小代码连接数据库

<%@ Page language="c#"  codePage="65001"%>
<%@ Import Namespace="System.Data" %>
<%@ Import Namespace="System.Data.SqlClient" %>
<%@ Import Namespace="System.Web" %>
<%@ Import Namespace="System.Web.SessionState" %>
<%@ Import Namespace="System.Web.UI" %>
<%@ Import Namespace="System.Web.UI.WebControls" %>
<%@ Import Namespace="System.Web.UI.HtmlControls" %>
<%@ Import Namespace="System.ComponentModel" %>
<%@ Import Namespace="System.Collections" %>
<%
//更新街道交叉口经纬度信息到数据库，如果没有，则插入，有则更新
// 用法： street1=华山路 & street2=衡山路 & lng=11111&lat=4444
System.Web.HttpContext context = this.Context;
System.Text.StringBuilder sb=new System.Text.StringBuilder();
 context.Response.AddHeader("Prama","no-cache");
            context.Response.CacheControl="private";
            context.Response.Expires=0;
            
             context.Response.ContentType="text/html";     
          
             //获取参数
             string street1=Request["street1"];  
             string street2=Request["street2"];
             string lng        =Request["lng"];
             string lat        =Request["lat"];
             
             if(street1==null) {street1="";}
             if(street2==null) {street2="";}
             if(lng==null) {lng="";}
             if(lat==null) {lat="";}
              
       
                     //获取数据
             DataSet ds = new DataSet(); 
             int r=0;
            string  sql="";
            string msgsuccess="操作成功<br/>";
            string msgerror="不成功，没有记录<br/>";
            string conn = "server=(local);database=callmeal;Uid=sa;Pwd=yyy;";
            SqlConnection con = new SqlConnection(conn);
            
             sql=" select *  from street";  
             context.Response.Write(sql); 
             SqlCommand   _cmd=new   SqlCommand(); 
             SqlDataAdapter da = new SqlDataAdapter(sql,conn);
             da.Fill(ds); 
             con.Open();                  
                _cmd.Connection =con;
                 
               //更新数据
                          sql=" update street set lng=11 where streetid=1" 
                          _cmd.CommandText=sql;
                        r=_cmd.ExecuteNonQuery(); 
                    if(r==-1) 
                        context.Response.Write(msgerror); 
                    else
                        context.Response.Write(msgsuccess);  
                              
            con.Close();   
                       
         
          //context.Response.Write(sql);
                      //context.Response.Write(sb.ToString()); 
             context.Response.Flush();
            context.Response.Close();

 
 %>