Asp.Net MVC 学习心得 之 View

一、使用View Data

首先要在Controller里加代码：

    public class ProductController : Controller
    {
        //
        // GET: /Product/

        public ActionResult Index()
        {
            ViewData["Message"] = "Hello World";
            return View();
        }

    }

然后在View里添加代码：

<%@ Page Title="" Language="C#" MasterPageFile="~/Views/Shared/Site.Master" Inherits="System.Web.Mvc.ViewPage<ToyStore.Models.Products>" %>

<asp:Content ID="Content1" ContentPlaceHolderID="TitleContent" runat="server">
    Index
</asp:Content>

<asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server">

    <h2>Index</h2>
    <%=ViewData["Message"] %>
</asp:Content>

内容就被传递了，但这样由于传入的值可能是任何类型的，所以你要自己做类型转换了，哈哈。

ViewData.Model是可以让你有个强类型的

ViewData.Model = _dataModel.ProductSet.ToList(); 

二、预防javascript注入攻击

默认是预防的，如果不想使用看下面的代码：

[ValidateInput(false)]  
[AcceptVerbs(HttpVerbs.Post)]  
public ActionResult Create([Bind(Exclude="Id")]Product productToCreate)  
{  
    if (!ModelState.IsValid)  
        return View();  
  
    try  
    {  
        _dataModel.AddToProductSet(productToCreate);  
        _dataModel.SaveChanges();  
  
        return RedirectToAction("Index");  
    }  
    catch  
    {  
        return View();  
    }  
} 

主要是那个[ValidateInput(false)]

三、可替换的View Engine

Asp.net Mvc里的View Engine是可以替换的，默认的engine是叫做Web Forms View Engine.现在已经有几个开源的View Engine了

http://www.codeplex.com/MVCContrib 可以到这里找找看，一个网站可以同时使用几个View Engine，可以在Global.asax里配置，使用不同的扩展名来区分使用不同View Engine 比如：.aspx页面就使用Web Forms View Engine.

我们也可以自定义一个View Engine,从VirtualPathProviderViewEngine 继承出一个类就可以了。

using System.Web.Mvc;  
  
namespace MvcApplication1.MyViewEngines  
{  
    public class SimpleViewEngine : VirtualPathProviderViewEngine  
    {  
        public SimpleViewEngine()  
        {  
            this.ViewLocationFormats = new string[] { "~/Views/{1}/{0}.simple", "~/Views/Shared/{0}.simple"};  
            this.PartialViewLocationFormats = new string[] { "~/Views/{1}/{0}.simple", "~/Views/Shared/{0}.simple" };  
        }  
  
        protected override IView CreateView(ControllerContext controllerContext, string viewPath, string masterPath)  
        {  
            var physicalPath = controllerContext.HttpContext.Server.MapPath(viewPath);  
            return new SimpleView(physicalPath);  
        }  
  
        protected override IView CreatePartialView(ControllerContext controllerContext, string partialPath)  
        {  
            var physicalPath = controllerContext.HttpContext.Server.MapPath(partialPath);  
            return new SimpleView(physicalPath);  
        }  
    }  
} 

在Global.asax里这样写

protected void Application_Start()  
{  
    RegisterRoutes(RouteTable.Routes);  
  
    ViewEngines.Engines.Add(new SimpleViewEngine());  
} 

然后自己写一个view的页面类：

namespace MvcApplication1.MyViewEngines  
{  
    public class SimpleView : IView  
    {  
        private string _viewPhysicalPath;  
  
        public SimpleView(string viewPhysicalPath)  
        {  
            _viewPhysicalPath = viewPhysicalPath;  
        }  
         
        #region IView Members  
  
        public void Render(ViewContext viewContext, TextWriter writer)  
        {  
            // Load file  
            string rawContents = File.ReadAllText(_viewPhysicalPath);  
  
            // Perform replacements  
            string parsedContents = Parse(rawContents, viewContext.ViewData);  
  
            // Write results to HttpContext  
            writer.Write(parsedContents);  
        }  
 
        #endregion  
  
        public string Parse(string contents, ViewDataDictionary viewData)  
        {  
            return Regex.Replace(contents, "\\{(.+)\\}",m => GetMatch(m, viewData));  
        }  
  
        protected virtual string GetMatch(Match m, ViewDataDictionary viewData)  
        {  
            if (m.Success)  
            {  
                string key = m.Result("$1");  
                if (viewData.ContainsKey(key))  
                {  
                    return viewData[key].ToString();  
                }  
            }  
            return string.Empty;  
        }  
      
    }  
}

定义一个Controller：

using System.Web.Mvc;  
  
namespace MvcApplication1.Controllers  
{  
    public class SimpleController : Controller  
    {  
        public ActionResult Index()  
        {  
            ViewData["message"] = "Hello World!";  
            return View();  
        }  
    }  
}

而页面可以写成：Views\Simple\Index.simple

<html>  
  
<head><title>Index Simple View</title></head>  
  
<body>  
  
<h1>{message}</h1>  
  
</body>  
  
</html>  

主要看{message}被解析出来了

注：上面的代码是从别人书里炒来的，不好意思

在View里有个HtmlHelper的东西 以后再写。