异常System.Web.HttpException (0x80004005): Server cannot set status after HTTP headers have been sent.

在用mvc 的AuthorizeAttribute做身份验证，重写HandleUnauthorizedRequest方法，在Application_Error方法里出现异常System.Web.HttpException (0x80004005): Server cannot set status after HTTP headers have been sent。

反复尝试发现是在 protected override void HandleUnauthorizedRequest(AuthorizationContext filterContext)方法里这行代码引起的"Base.HandleUnauthorizedRequest(filterContext)"。删除该代码,发现在跳转前还是会执行Action里的其它方法。

改用： filterContext.Result = new RedirectResult(Common.GOMELONGINGURL);

一切正常。