如何初始化IOption 以便对.NET核心MVC服务进行单元测试？

I have a .NET core MVC rest service. I have a controller I wish to test. This controller has a constructor argument of IOptions where AppSettings is my class for config settings ( I store my database connection string in it). It gets injected from the setup in ConfigureServices in Startup.csI have a .NET core MVC rest service. I have a c