ASP.NET MVC中將控制器分離到類庫的實現

// 源文件頭信息：
// <copyright file="ControllersFactory.cs">
// Copyright(c)2014-2034 Kencery.All rights reserved.
// 創建人：韓迎龍(kencery)
// 創建時間：2015-6-18
// </copyright>

using System;
using System.Reflection;
using System.Web.Mvc;
using System.Web.Routing;
using System.Web.SessionState;

namespace BookSystem_Controllers
{
 /// <summary>
 /// 重寫注冊控制器的方法，使之能夠將控制器管分離到其它類庫中實現
 /// <auther>
 /// <name>kencery</name>
 /// <date>2015-6-18</date>
 /// </auther>
 /// </summary>
 /// 說明：IControllerFactory接口含有三個需要實現的方法：CreateController，GetControllerSessionBehavior，ReleaseController
 /// 使用：在MVC App_Start文件夾中的RouteConfig中的方法RegisterRoutes中的第一行中寫入下面注冊語句,Global.asax中也可注冊，放到注冊路由之前即可
 /// ControllerBuilder.Current.SetControllerFactory(new ControllersFactory("BookSystem_Controllers")); //BookSystem_Controllers為控制器的類庫
 public class ControllersFactory : IControllerFactory
 {
 private readonly string _assemblyName;
 private readonly string _controlerDefaultNameSpage;
 private Assembly _controllerAssembly;

 /// <summary>
 /// 獲取控制器所在的程序集名稱
 /// </summary>
 public string AssemblyName
 {
 get { return _assemblyName; }
 }

 /// <summary>
 /// 獲取控制器的默認命名空間
 /// </summary>
 public string ControlerDefaultNameSpage
 {
 get { return _controlerDefaultNameSpage; }
 }

 /// <summary>
 /// 獲取控制器所在的程序集的Assembly實例
 /// </summary>
 public Assembly ControllerAssembly
 {
 get
 {
 return _controllerAssembly ?? (_controllerAssembly = Assembly.Load(AssemblyName)); //加載控制器信息
 }
 }

 /// <summary>
 /// 構造函數實例化
 /// </summary>
 /// <param name="assemblyName"></param>
 public ControllersFactory(string assemblyName)
 {
 _assemblyName = assemblyName;
 }

 /// <summary>
 /// 構造函數實例化
 /// </summary>
 /// <param name="assemblyName"></param>
 /// <param name="controlerDefaultNameSpage"></param>
 public ControllersFactory(string assemblyName, string controlerDefaultNameSpage)
 {
 _assemblyName = assemblyName;
 _controlerDefaultNameSpage = controlerDefaultNameSpage;
 }

 /// <summary>
 /// 獲取控制器類的全名
 /// </summary>
 /// <param name="controllerName">控制器名稱</param>
 public string GetControllerFullName(string controllerName)
 {
 return string.Format("{0}.{1}Controller",
 string.IsNullOrEmpty(ControlerDefaultNameSpage) ? AssemblyName : ControlerDefaultNameSpage,
 controllerName);
 }

 /// <summary>
 /// 獲取控制器實例對象，根據controllerName生成一個沒有請求上下文對象的空的控制器，在為此控制器制定ControllerContext對象，然后返回控制器實例
 /// </summary>
 /// <param name="requestContext"></param>
 /// <param name="controllerName"></param>
 public IController CreateController(RequestContext requestContext, string controllerName)
 {
 var controller = ControllerAssembly.CreateInstance(GetControllerFullName(controllerName)) as Controller;
 if (controller == null)
 return null;
 if (controller.ControllerContext == null)
 {
 controller.ControllerContext = new ControllerContext(requestContext, controller);
 }
 else
 {
 controller.ControllerContext.RequestContext = requestContext;
 }
 return controller;
 }

 /// <summary>
 /// 返回請求的會話狀態的支持類型
 /// </summary>
 /// <param name="requestContext"></param>
 /// <param name="controllerName"></param>
 public SessionStateBehavior GetControllerSessionBehavior(RequestContext requestContext, string controllerName)
 {
 var controllerType = ControllerAssembly.GetType(GetControllerFullName(controllerName), true, true);
 var sessionStateAttr =
 Attribute.GetCustomAttribute(controllerType, typeof (SessionStateAttribute), false) as
 SessionStateAttribute;
 return sessionStateAttr == null ? SessionStateBehavior.Default : sessionStateAttr.Behavior;
 }

 /// <summary>
 /// 釋放資源
 /// </summary>
 /// <param name="controller"></param>
 public void ReleaseController(IController controller)
 {
 var idDisposable = controller as IDisposable;
 if (idDisposable != null)
 {
 idDisposable.Dispose();
 }
 }
 }
}

//系統默認路由
 routes.MapRoute(
 name: "Default",
 url: "{controller}/{action}/{id}",
 defaults: new {controller = "Login", action = "Index", id = UrlParameter.Optional},
 namespaces: new string[] {"BookSystem_Controllers"}
);