常规的
1.
<appSettings>
<add key="connStr" value="Data Source=(local);Initial Catalog=test;Persist Security Info=True;User ID=sa;Password=sa"/>
</appSettings>
调用
System.Configuration.ConfigurationManager.AppSettings["connStr"];
2.
<connectionStrings>
<add name="connStr" connectionString="data source=机器名/SQLEXPRESS;uid=sa;pwd=123456;initial catalog=test" providerName="System.Data.SqlClient"/>
调用
public static readonly string txtConnecttionString = ConfigurationManager.ConnectionStrings["connStr"].ConnectionString;