Support MultipleActiveResultSets=false?

[LeiYangGH]

This demo is great and I want to integrate the role manage functions in my project.

In connection string, MultipleActiveResultSets=true is a feature of sqlserver, if set to false, openning RolesManage page will get exception such as

InvalidOperationException: There is already an open DataReader associated with this Command which must be closed first.

And if i use MySql, there's no way to set MultipleActiveResultSets=true(not supported at all, web app cannot start).

So I think somewhere in UserRolesController.cs could be improved to avoid this exception. But I'm not yet able to fix myself. Could you have a look?