SqlConnection连SQL数据库通过web.config获取数据源

using  System;
using  System.Data;
using  System.Data.SqlClient;
using  System.Configuration;

namespace  simx
... {
    public class lj:System.Web.UI.Page
    ...{
        private void Page_Load(object sender,System.EventArgs e)
        ...{
            if(!Page.IsPostBack)
            ...{
               getdata();
            }
        }

        private void InitializeComponent()
        ...{
        
        }
    
        private void getdata()
        ...{
           string sqlconn=ConfigurationSettings.AppSettings["CONN_STRING"];
           SqlConnection conn=new SqlConnection(sqlconn);
           conn.Open();
        }
    }
}


// web.config文件
< appSettings >
     < add key = " CONN_STRING "  value = " Server=(lIP地址);User id=用户名;Pwd=密码;Database=数据库 " ></ add >
</ appSettings >