为什么System.Web.HttpContext.Current.User在控制器构造函数期间解析，但User.Identity不能解析

Question

Rowan Freeman's answer to this question describes why User.Identity is null during the constructor of a controller. A comment on the same question points out that System.Web.HttpContext.Current.User does result in the expected value in the same context.

Why is System.Web.HttpContext.Current.User valid during the controller's constructor even though User.Identity is not?

Will using System.Web.HttpContext.Current during the constructor of a controller potentially result in bugs?

Edit for clarification:

From the linked article, regarding User.Identity : "Controller instantiation will occur before authorization takes place. Even if your MVC application calls RenderAction() several times and you end up creating say, five different controllers, those five controllers will be created before any OnAuthorization takes place."

Does the above paragraph not apply to System.Web.HttpContext.Current ? I am hoping to better understand the nuance between the two that makes them appear to behave differently, to hopefully understand whether System.Web.HttpContext.Current is acceptable to use outside of an individual action but inside the controller.

Answer 1

Will using System.Web.HttpContext.Current during the constructor of a controller potentially result in bugs?

It will introduce an undesirable dependency, which will, for example, prevent you from being able to unit test the controller properly.

You might consider overriding Controller.Initialize instead to add your own initializ