CRUD全栈式编程架构之MVC的扩展设计

MVC执行流程

路由的扩展

我理解的路由作用有以下几个

•  Seo优化，用“/”分开的url爬虫更爱吃
•  物理和逻辑文件分离,url不再按照文件路径映射
•  Controller，Action的选择

MVC路由的扩展

实话实说MVC的路由我很少去做扩展，在MVC4时代，还会去重写掉url的大小写，而在MVC5之后，MVC自带了配置去小写化url。不过有一个配置还是必须要提一下那就是Area，在你的系统达到一定规模之后，Controllers通过Area来管理将会变得更容易。这里给出我的Area扩展，很简单但是很重要,注意子类必须以AreaRegistration结尾，同样遵循约定有限于配置的原则，当然你也可以重写。

public abstract class AreaRegistrationBase : AreaRegistration
   {
       public override string AreaName
       {
           get {
               var item = GetType().Name;
               return item.Replace("AreaRegistration", "");
           }
       }

       public override void RegisterArea(AreaRegistrationContext context)
       {
            context.MapLowerCaseUrlRoute(
            AreaName + "_default",
            AreaName.ToLower() + "/{controller}/{action}/{id}",
            new { action = "Index", id = UrlParameter.Optional }
            );
            GlobalConfiguration.Configuration.Routes.MapHttpRoute(
                AreaName + "Api",
                "api/" + AreaName + "/{controller}/{action}/{id}",
                new { area = AreaName, id = RouteParameter.Optional, namespaceName = new[] { this.GetType().Namespace } }
            );
       }
   }

WebApi路由的扩展

上面MVC的路由也注册了Api的路由，当然还有更好的方法，由于WebApi,基本不需要Url.Action和HtmlAction，这种路由出栈的策略，不需要去通过路由生成Url,所以
我们只需要做到路由的解析即可，并且webapi并没有提供自带的area机制，所以我扩展了DefaultHttpControllerSelector，获取到路由中area和controller参数
然后完成拼接，然后反射类型查找，在最开始时候预先缓存了所有controller，所以性能还不错，由于原代码是反编译获得，所以linq部分有点糟糕，等我回公司拿到源代码再修改。

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net.Http;
using System.Text;
using System.Web.Http;
using System.Web.Http.Controllers;
using System.Web.Http.Dispatcher;

namespace Coralcode.Webapi.Route
{
  public class AreaHttpControllerSelector : DefaultHttpControllerSelector
  {
    public static string CoralControllerSuffix = "ApiController";
    private readonly HttpConfiguration _configuration;
    private readonly Lazy<ILookup<string, Type>> _apiControllerTypes;

    private ILookup<string, Type> ApiControllerTypes
    {
      get
      {
        return this._apiControllerTypes.Value;
      }
    }

    public AreaHttpControllerSelector(HttpConfiguration configuration)
      : base(configuration)
    {
      this._configuration = configuration;
      this._apiControllerTypes = new Lazy<ILookup<string, Type>>(new Func<ILookup<string, Type>>(this.GetApiControllerTypes));
    }

    private ILookup<string, Type> GetApiControllerTypes()
    {
      return Enumerable.ToLookup<Type, string, Type>((IEnumerable<Type>) ServicesExtensions.GetHttpControllerTypeResolver(this._configuration.Services).GetControllerTypes(ServicesExtensions.GetAssembliesResolver(this._configuration.Services)), (Func<Type, string>) (t => t.Name.ToLower().Substring(0, t.Name.Length - AreaHttpControllerSelector.CoralControllerSuffix.Length)), (Func<Type, Type>) (t => t));
    }

    public override HttpControllerDescriptor SelectController(HttpRequestMessage request)
    {
      string controllerName = this.GetControllerName(request);
      if (!string.IsNullOrWhiteSpace(controllerName))
      {
        List<Type> list = Enumerable.ToList<Type>(this.ApiControllerTypes[controllerName.ToLower()]);
        if (Enumerable.Any<Type>((IEnumerable<Type>) list))
        {
          IDictionary<string, object> values = HttpRequestMessageExtensions.GetRouteData(request).Values;
          string endString;
          if (values.Count > 1)
          {
            StringBuilder stringBuilder = new StringBuilder();
            if (values.ContainsKey("area"))
            {
              stringBuilder.Append('.');
              stringBuilder.Append(values["area"]);
              stringBuilder.Append('.');
              stringBuilder.Append("controllers");
            }
            if (values.ContainsKey("controller"))
            {
              stringBuilder.Append('.');
              stringBuilder.Append(values["controller"]);
              stringBuilder.Append(AreaHttpControllerSelector.CoralControllerSuffix);
            }
            endString = stringBuilder.ToString();
          }
          else
            endString = string.Format(".{0}{1}", (object) controllerName, (object) AreaHttpControllerSelector.CoralControllerSuffix);
          Type controllerType = Enumerable.FirstOrDefault<Type>((IEnumerable<Type>) Enumerable.OrderBy<Type, int>(Enumerable.Where<Type>((IEnumerable<Type>) list, (Func<Type, bool>) (t => t.FullName.EndsWith(endString, StringComparison.CurrentCultureIgnoreCase))), (Func<Type, int>) (t => Enumerable.Count<char>((IEnumerable<char>) t.FullName, (Func<char, bool>) (s => (int) s == 46)))));
          if (controllerType != (Type) null)
            return new HttpControllerDescriptor(this._configuration, controllerName, controllerType);
        }
      }
      return base.SelectController(request);
    }
  }
}

Controller激活

Controller激活这部分是MVC和Ioc结合的核心，Ioc有三大部分

•  Register 类型的发现和注册，解决如何发现那些类型是需要注册的和如何注册，这里我采用Attribute的方式去发现，用Unity自带的注册方法注册
•  Resolve  类型的解析,如何知道某个类型和将其实例化
•  LiftTime  如何控制实例的生命周期，例如是否使用单例，生命周期也采用Unity自带的，主要用到单例和每次解析都一个实例

MVC需要和Ioc激活首先我们关注的就是哪里注册和哪里去实例化，由于MVC使用的是约定优先于配置的方式，所有的Controller都是以“Controller”结尾，所以这里我直接加载
程序集，然后找到所有类型以Controller结尾的去注册就好了，激活的话有以下三种方式，难易程度依次递增，嵌套深度也依次递增，这里我采用重写
默认DefaultControllerFactory的方式去激活，这样既可以用自己的也结合其他机制去实现,其他方式大家可以自行扩展。

•  ControllerFactory
•  IControllerActivetor
•  IDependencyResolver

using Coralcode.Framework.Aspect.Unity;
using Coralcode.Mvc.Resources;
using System;
using System.Web;
using System.Web.Mvc;
using System.Web.Routing;

namespace Coralcode.Mvc.ControllerFactory
{
  public class UnityControllerFactory : DefaultControllerFactory
  {
    public override IController CreateController(RequestContext requestContext, string controllerName)
    {
      return base.CreateController(requestContext, controllerName);
    }

    protected override IController GetControllerInstance(RequestContext requestContext, Type controllerType)
    {
      if (controllerType == (Type) null)
        throw new HttpException(404, Messages.MvcBase_NotFoundPage);
      if (!UnityService.HasRegistered(controllerType))
        return base.GetControllerInstance(requestContext, controllerType);
      return (IController) UnityService.Resolve(controllerType);
    }
  }
}
//webapi 激活如下

using Coralcode.Framework.Aspect.Unity;
using System;
using System.Net.Http;
using System.Web.Http.Controllers;
using System.Web.Http.Dispatcher;

namespace Coralcode.Webapi.ControllerFactory
{
  public class UnityControllerActivator : IHttpControllerActivator
  {
    public IHttpController Create(HttpRequestMessage request, HttpControllerDescriptor controllerDescriptor, Type controllerType)
    {
      IHttpController httpController = (IHttpController) UnityService.Resolve(controllerType);
      HttpRequestMessageExtensions.RegisterForDispose(request, httpController as IDisposable);
      return httpController;
    }
  }
}

Filter执行

LogFilter

这里基本上都是Mvc的源代码，只是增加了一个日志功能而已，扒MVC源代码大家一定去尝试

using Coralcode.Framework.Log;
using System;
using System.Web;
using System.Web.Mvc;

namespace Coralcode.Mvc.Filters
{
  [AttributeUsage(AttributeTargets.Class | AttributeTargets.Method)]
  public class LogExceptionAttribute : HandleErrorAttribute
  {
    public override void OnException(ExceptionContext filterContext)
    {
      if (filterContext == null)
        throw new ArgumentNullException("filterContext");
      Exception exception = filterContext.Exception;
      LoggerFactory.Instance.Error(exception.ToString());
      if (filterContext.IsChildAction || filterContext.ExceptionHandled || (!filterContext.HttpContext.IsCustomErrorEnabled || new HttpException((string) null, exception).GetHttpCode() != 500) || !this.ExceptionType.IsInstanceOfType((object) exception))
        return;
      this.HandlerViewResultException(filterContext);
    }

    private void HandlerViewResultException(ExceptionContext filterContext)
    {
      string controllerName = (string) filterContext.RouteData.Values["controller"];
      string actionName = (string) filterContext.RouteData.Values["action"];
      HandleErrorInfo model = new HandleErrorInfo(filterContext.Exception, controllerName, actionName);
      ExceptionContext exceptionContext = filterContext;
      ViewResult viewResult1 = new ViewResult();
      viewResult1.ViewName = this.View;
      viewResult1.MasterName = this.Master;
      viewResult1.ViewData = (ViewDataDictionary) new ViewDataDictionary<HandleErrorInfo>(model);
      viewResult1.TempData = filterContext.Controller.TempData;
      ViewResult viewResult2 = viewResult1;
      exceptionContext.Result = (ActionResult) viewResult2;
      filterContext.ExceptionHandled = true;
      filterContext.HttpContext.Response.Clear();
      filterContext.HttpContext.Response.StatusCode = 500;
      filterContext.HttpContext.Response.TrySkipIisCustomErrors = true;
    }
  }
}

ResultFilter

这里统一处理了Ajax请求返回数据以ResultMessage返回，如果不是JsonResult选择忽略,具体设计初衷可以看Controller设计那一节.

using Coralcode.Framework.Models;
using Coralcode.Mvc.ActionResults;
using System.Web.Mvc;

namespace Coralcode.Mvc.Filters
{
  public class ResultMessageAttribute : ActionFilterAttribute
  {
    public override void OnResultExecuting(ResultExecutingContext filterContext)
    {
      JsonResult jsonResult = (JsonResult) (filterContext.Result as CustomJsonResult) ?? filterContext.Result as JsonResult;
      if (jsonResult == null)
        return;
      jsonResult.Data = this.GetResultMessage(jsonResult.Data);
      filterContext.Result = (ActionResult) jsonResult;
    }

    private object GetResultMessage(object data)
    {
      if (data is BaseMessage)
        return data;
      return (object) new ResultMessage(ResultState.Success, "Success", data);
    }
  }
}

Action执行

提高并发利器，最佳使用方式，这里详细的介绍可以结合Artec的Controller同步和异步这一节,其中我个人推荐的就是采用返回Task<ActionResult>。

ValueProvider和ModelBinder

这里会将Url中的参数作为Model绑定的数据源。在做三级菜单的时候可以体现出用途,例如我首先在数据字典中添加如下数据

var newsType = new Glossary()
           {
               Key = "NewsType",
               Value = "NewsType",
               Description = "新闻",
               Seq = 0,
               Title = "新闻类型",
               ParentId = -1,
           };
           _glossaryService.Add(newsType);
           _glossaryService.Add(new Glossary()
           {
               Key = "RecentNews",
               Value = "RecentNews",
               Description = "新闻类型",
               Seq = 1,
               Title = "最新活动",
               ParentId = newsType.Id,
           });
           _glossaryService.Add(new Glossary()
           {
               Key = "UserActivity",
               Value = "UserActivity",
               Description = "新闻类型",
               Seq = 2,
               Title = "会员活动",
               ParentId = newsType.Id,
           });
           _glossaryService.Add(new Glossary()
           {
               Key = "OnlineMarket",
               Value = "OnlineMarket",
               Description = "新闻类型",
               Seq = 3,
               Title = "在线商城",
               ParentId = newsType.Id,
           });
           _glossaryService.Add(new Glossary()
           {
               Key = "AboutUs",
               Value = "AboutUs",
               Description = "新闻类型",
               Seq = 4,
               Title = "关于我们",
               ParentId = newsType.Id,
           });
           Repository.UnitOfWork.Commit();

 然后从字段中读出数据去添加菜单

var newsMenu = Regist("新闻管理", "/portal/home/handerindex?menuId=" + systemManagerMenu.Identify + "-NewsType",
             systemManagerMenu.Identify, systemManagerMenu.Identify + "-NewsType");
         //新闻管理
         _glossaryService.GetFiltered("新闻类型").ForEach(item =>
         {
             Regist(item.Title,string.Format( "/portal/news/index?typeid={0}&type={1}" , item.Id,item.Title),
                 newsMenu.Identify, newsMenu.Identify + "-" + item.Id);
         });

 加载三级菜单

      /// <summary>
      /// 处理界面
      /// </summary>
      /// <returns></returns>
      public ActionResult HanderIndex(string menuId)
      {
          ViewBag.Tree = string.Empty;
          //TODO:请求两次，待处理
          if (menuId == null)
              return View();
          var items = _menuService.GetChildrenMenus(menuId);

          ViewBag.Tree = JsonConvert.SerializeObject(items);

          return View();
      } 

 界面如图

然后在Search和ViewModel中有一个字段是TypeId，这样在List,PageSearch，AddOrEdit中就可以自动绑定值了。 

public  class NewsSearch:SearchBase
   {

       public long? TypeId { get; set; }
       

       public string Title { get; set; }
   }

View发现和ActionResult执行

MVC默认的系统比较弱，当controller和view比较多的时候一个文件下面内容会非常多，我这里做了一个模块化处理.

using System.Web.Mvc;

namespace Coralcode.Mvc.ViewEngines
{
  public class ThemesRazorViewEngine : RazorViewEngine
  {
    public ThemesRazorViewEngine()
    {
      this.AreaViewLocationFormats = new string[3]
      {
        "~/Themes/{2}/{1}/{0}.cshtml",
        "~/Themes/Shared/{0}.cshtml",
        "~/Themes/{2}/Shared/{0}.cshtml"
      };
      this.AreaMasterLocationFormats = new string[1]
      {
        "~/Themes/Shared/{0}.cshtml"
      };
      this.AreaPartialViewLocationFormats = new string[4]
      {
        "~/Themes/{2}/{1}/{0}.cshtml",
        "~/Themes/{2}/Shared/{0}.cshtml",
        "~/Themes/Shared/{0}.cshtml",
        "~/Themes/Shared/Control/{0}.cshtml"
      };
      this.ViewLocationFormats = new string[2]
      {
        "~/Themes/{1}/{0}.cshtml",
        "~/Themes/Shared/{0}.cshtml"
      };
      this.MasterLocationFormats = new string[1]
      {
        "~/Themes/Shared/{0}.cshtml"
      };
      this.PartialViewLocationFormats = new string[2]
      {
        "~/Themes/{1}/{0}.cshtml",
        "~/Themes/Shared/{0}.cshtml"
      };
    }

    public override ViewEngineResult FindView(ControllerContext controllerContext, string viewName, string masterName, bool useCache)
    {
      if (controllerContext.RouteData.Values.ContainsKey("area") && !controllerContext.RouteData.DataTokens.ContainsKey("area"))
        controllerContext.RouteData.DataTokens.Add("area", controllerContext.RouteData.Values["area"]);
      return base.FindView(controllerContext, viewName, masterName, useCache);
    }
  }

 项目目录结构如下图

这样子发布后的目录非常的干净，如图：

JsonResult执行和MetaData(模型元数据提供机制)

这部分在Controller设计那一节有详细说明，请往前一步参考

总结

•  大家一定要看看MVC源代码，
•  脑袋里要能把MVC执行流程串起来
•  主体设计已经讲完了，源代码整理中，工作比较忙，见谅，
•  喜欢请关注，有问题请留言，头疼得一笔，睡觉，晚安