ASP.NET MVC 2扩展点之Model Binder实例分析

MVC 2的Model可以是任意一个类。
许多教程只讲“ADO.NET实体数据模型”Model1.edmx
然后连接mssql2005以上，自动生成数据模型。
这样会让初学者不能更好地理解Model与View之间的关系。
这里我详细介绍一下怎样用任意一个类做Model，
这样你也可以在MVC项目中使用Access数据库，任意数据库吧。

步骤：新建MVC项目
删除默认生成的Controller,View，我喜欢简洁，突出重点。
右击Models目录，新建Book.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

namespace MvcModelBinder.Models
{
    public class Book
    {
        public string Title { get; set; }
        public string Author { get; set; }
        public DateTime DatePublished { get; set; }
    }
}

 

同上，新建BookModelBinder.cs，这样你就可以像“ADO.NET实体数据模型”使用任意类做Model了。

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

using System.Web.Mvc;//IModelBinder命名空间

namespace MvcModelBinder.Models
{
    public class BookModelBinder : IModelBinder
    {

        public object BindModel(ControllerContext controllerContext, ModelBindingContext bindingContext)
        {
            var book = (Book)(bindingContext.Model ?? new Book());
            book.Title = GetValue<string>(bindingContext, "Title");
            book.Author = GetValue<string>(bindingContext, "Author");
            book.DatePublished = GetValue<DateTime>(bindingContext, "DatePublished");
            if (String.IsNullOrEmpty(book.Title))
            {
                bindingContext.ModelState.AddModelError("Title", "书名不能为空?");
            }

            return book;
        }


        private T GetValue<T>(ModelBindingContext bindingContext, string key)
        {
            ValueProviderResult valueResult = bindingContext.ValueProvider.GetValue(key);
            bindingContext.ModelState.SetModelValue(key, valueResult);
            return (T)valueResult.ConvertTo(typeof(T));
        }
    }
}

 

新建BookController.cs这里提交添加表单的时候，把数据保存在TempData中。

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;

using MvcModelBinder.Models;

namespace MvcModelBinder.Controllers
{
    public class BookController : Controller
    {
        #region 添加的代码

        public ActionResult List()
        {
            List<Book> bookList = new List<Book>();

            Book book = new Book();
            book.Title = "书名";
            book.Author = "作者";
            book.DatePublished = DateTime.Now;
            bookList.Add(book);

            if (TempData["NewBook"] != null)
            {
                Book newBook = TempData["NewBook"] as Book;
                bookList.Add(newBook);
            }

            return View(bookList);
        }

        //
        // GET: /Book/Create

        public ActionResult Create()
        {
            return View();
        }

        //
        // POST: /Book/Create

        [HttpPost]
        public ActionResult Create(Book book)
        {
            try
            {
                // TODO: Add insert logic here
                Book newBook = new Book();
                newBook.Author = book.Author;
                newBook.Title = book.Title;
                newBook.DatePublished = book.DatePublished;
                TempData["NewBook"] = book;

                return RedirectToAction("List");
            }
            catch
            {
                return View();
            }
        }

        #endregion

        //
        // GET: /Book/

        public ActionResult Index()
        {
            return View();
        }

        //
        // GET: /Book/Details/5

        public ActionResult Details(int id)
        {
            return View();
        }
        
        //
        // GET: /Book/Edit/5
 
        public ActionResult Edit(int id)
        {
            return View();
        }

        //
        // POST: /Book/Edit/5

        [HttpPost]
        public ActionResult Edit(int id, FormCollection collection)
        {
            try
            {
                // TODO: Add update logic here
 
                return RedirectToAction("Index");
            }
            catch
            {
                return View();
            }
        }

        //
        // GET: /Book/Delete/5
 
        public ActionResult Delete(int id)
        {
            return View();
        }

        //
        // POST: /Book/Delete/5

        [HttpPost]
        public ActionResult Delete(int id, FormCollection collection)
        {
            try
            {
                // TODO: Add delete logic here
 
                return RedirectToAction("Index");
            }
            catch
            {
                return View();
            }
        }
    }
}

 

新建View：List.aspx,Create.aspx这里创建强类型视图，可以选择Book
Create.aspx

<%@ Page Language="C#" Inherits="System.Web.Mvc.ViewPage<MvcModelBinder.Models.Book>" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>Create</title>
</head>
<body>
    <% using (Html.BeginForm()) {%>
        <%: Html.ValidationSummary(true) %>

        <fieldset>
            <legend>Fields</legend>
            
            <div class="editor-label">
                <%: Html.LabelFor(model => model.Title) %>
            </div>
            <div class="editor-field">
                <%: Html.TextBoxFor(model => model.Title) %>
                <%: Html.ValidationMessageFor(model => model.Title) %>
            </div>
            
            <div class="editor-label">
                <%: Html.LabelFor(model => model.Author) %>
            </div>
            <div class="editor-field">
                <%: Html.TextBoxFor(model => model.Author) %>
                <%: Html.ValidationMessageFor(model => model.Author) %>
            </div>
            
            <div class="editor-label">
                <%: Html.LabelFor(model => model.DatePublished) %>
            </div>
            <div class="editor-field">
                <%: Html.TextBoxFor(model => model.DatePublished) %>
                <%: Html.ValidationMessageFor(model => model.DatePublished) %>
            </div>
            
            <p>
                <input type="submit" value="Create" />
            </p>
        </fieldset>

    <% } %>

    <div>
        <%: Html.ActionLink("Back to List", "Index") %>
    </div>

</body>
</html>

 

List.aspx

<%@ Page Language="C#" Inherits="System.Web.Mvc.ViewPage<IEnumerable<MvcModelBinder.Models.Book>>" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>List</title>
</head>
<body>
    <table>
        <tr>
            <th></th>
            <th>
                Title
            </th>
            <th>
                Author
            </th>
            <th>
                DatePublished
            </th>
        </tr>

    <% foreach (var item in Model) { %>
    
        <tr>
            <td>
                <%: Html.ActionLink("Edit", "Edit", new { /* id=item.PrimaryKey */ }) %> |
                <%: Html.ActionLink("Details", "Details", new { /* id=item.PrimaryKey */ })%> |
                <%: Html.ActionLink("Delete", "Delete", new { /* id=item.PrimaryKey */ })%>
            </td>
            <td>
                <%: item.Title %>
            </td>
            <td>
                <%: item.Author %>
            </td>
            <td>
                <%: String.Format("{0:g}", item.DatePublished) %>
            </td>
        </tr>
    
    <% } %>

    </table>

    <p>
        <%: Html.ActionLink("Create New", "Create") %>
    </p>

</body>
</html>

 

最后据说需要在Global.asax中注册，我没有注册一样不出错。可能哪里理解不到位。

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using System.Web.Routing;

using MvcModelBinder.Models;

namespace MvcModelBinder
{
    // 注意: 有关启用 IIS6 或 IIS7 经典模式的说明，
    // 请访问 http://go.microsoft.com/?LinkId=9394801

    public class MvcApplication : System.Web.HttpApplication
    {
        public static void RegisterRoutes(RouteCollection routes)
        {
            routes.IgnoreRoute("{resource}.axd/{*pathInfo}");

            routes.MapRoute(
                "Default", // 路由名称
                "{controller}/{action}/{id}", // 带有参数的 URL
                new { controller = "Book", action = "List", id = UrlParameter.Optional } // 参数默认值
            );

        }

        protected void Application_Start()
        {
            //据说需要这样注册一下，我不注册也不影响。不知道哪里理解不到位。
            ModelBinders.Binders.Add(typeof(Book), new BookModelBinder());

            AreaRegistration.RegisterAllAreas();

            RegisterRoutes(RouteTable.Routes);
        }
    }
}

 

这是最终的目录结构：

本文源码：https://files.cnblogs.com/greatverve/MvcModelBinder.rar

参考：http://www.cnblogs.com/zhuqil/archive/2010/07/31/you-have-to-knowextensibility-points-in-asp-net-mvc-model-binder.html

这里这个大牛，不屑过多解释，这个工作由我来做吧。