asp.net mvc的生命周期

asp.net mvc的生命周期主要分三个阶段
1、网址路由对比
2、找到对应的Controller执行相应的Action
3、执行View并返回结果

完整的生命周期
Request->UrlRoutingModule->RouteHandler->MvcHandler->
DefaultControllerFactory->Controller->View Factory->View->Response

执行control和view
当程序执行到MvcHandler,它的入口是ProcessRequest，在MvcHandler中的ProcessRequest

        protected internal virtual void ProcessRequest(HttpContextBase httpContext) {
            SecurityUtil.ProcessInApplicationTrust(() => {
                IController controller;
                IControllerFactory factory;
                ProcessRequestInit(httpContext, out controller, out factory);

                try {
                    controller.Execute(RequestContext);
                }
                finally {
                    factory.ReleaseController(controller);
                }
            });
        }
第一步：获取Controller,ControllerFactory

// 获取控制器的名称
string controllerName = RequestContext.RouteData.GetRequiredString("controller");

//获取控制器工厂，默认是DefaultControllerFactory
factory = ControllerBuilder.GetControllerFactory();

//创建控制器
controller = factory.CreateController(RequestContext, controllerName);


第二步：执行Controller的Action

 controller.Execute(RequestContext);
 最后调用Controller的ExecuteCore方法
        protected override void ExecuteCore() {
            // If code in this method needs to be updated, please also check the BeginExecuteCore() and
            // EndExecuteCore() methods of AsyncController to see if that code also must be updated.

            PossiblyLoadTempData();
            try {
                string actionName = RouteData.GetRequiredString("action");
                if (!ActionInvoker.InvokeAction(ControllerContext, actionName)) {
                    HandleUnknownAction(actionName);
                }
            }
            finally {
                PossiblySaveTempData();
            }
        }

第三步：执行View
如果从Action返回的是ViewResult,Mvc会调用实现IViewEngine对象的FindView方法，然后再调用实现IView（WebFormView）的Render()方法，将
Html返回给客户端