两种方式连接数据库

   public static readonly  string conn = ConfigurationManager.ConnectionStrings["connstr"].ConnectionString;

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<connectionStrings >
<add name ="connstr" connectionString ="Data Source=ZGC-20130925HMO;Initial Catalog=NonStructrueFiles;Integrated Security=true"/>
</connectionStrings>
</configuration>

string connStr = @"server=ZGC-20130925HMO\Administrator;database=Student;uid=sa;pwd=zjw377128183";
conn = new SqlConnection(connStr);

<connectionStrings >
<add name ="connstr" connectionString ="server=ZGC-20130925HMO\SQLEXPRESS;database=NonStructrueFiles;uid=sa;pwd=zjw377128183"/>
</connectionStrings>