獲取config文件配置的連接字符串
private static string connString = ConfigurationManager.AppSettings["ConnctionStr"].ToString();
//windows身份驗證使用的
<appSettings>
<add key="ConnctionStr" value="server=1.1.0.1;database=1;integrated security=true"/>
</appSettings>
//sql server登陸驗證所需要的
<appSettings>
<add key="ConnctionStr" value="server=1.1.0.1;database=1;integrated security=false;uid=sa;pwd=123"/>
</appSettings>
