我认为MvcApplication是一个全局的
singleton.我想在控制器中获取MvcApplication的实例。然后我把以下代码放在控制器中：
MvcApplication app = HttpContext.Current.Application as MvcApplication;
它给我一个错误：
Error 2 ‘System.Web.HttpContextBase’ does not contain a definition for ‘Current’ and no extension method ‘Current’ accepting a first argument of type ‘System.Web.HttpContextBase’ could be found (are you missing a using directive or an assembly reference?)
为什么？如何在控制器中访问MvcApplication？
解决方法
尝试这个：
var app = HttpContext.ApplicationInstance as MvcApplication;
