解决"There is already an open DataReader associated with this Command which must be closed first." exception in EF 中

当我开启惰性加载情况下，系统会报此异常信息，出现此异常是发生于Sql server 2005.

解决方法：在数据库连接字符串中添加MARS信息为true

<add name="CRGDatabase" connectionString="Data Source=./;Initial Catalog=DB;uid=User;pwd=Pwd;MultipleActiveResultSets=true;" providerName="System.Data.SqlClient"/>