asp.net连接数据库

在web.config里面添加连接字符串：

<?xml version="1.0" encoding="utf-8" ?><configuration>      <appSettings>     <add key="datalink" value="server=localhost;uid=sa;password=1234567890;database=demo"/>  </appSettings>

......

 

页面CS代码：

using System.Data.SqlClient;

string con = System.Configuration.ConfigurationSettings.AppSettings["datalink"];

或者

string con = ConfigurationSettings.AppSettings["dataLink"];

...

if(!Page.IsPostBack)   {    SqlConnection conn = new SqlConnection(con);    conn.Open();    Label1.Text=conn.State.ToString();

    conn.Close();    Label2.Text = conn.State.ToString();   }