自定義Html Helper在視圖中無法使用（Razor/Asp.Net MVC3）

Question

我試圖使用HtmlAgilityPack實現白名單HTML Sanitizer。我想創建一個可重用的Html Helper，允許我使用它。我有其他自定義的Html幫助程序，我正在使用該工作，但由於某種原因，這一個不起作用。每次我嘗試從視圖中調用它時，都無法找到Sanitize方法。我想打這個電話是在一個局部視圖，看起來像這樣：

@Html.Raw(Html.Sanitize(Model.Body)) 

我的HTML幫助器類：

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

namespace ProjectX.WebUI.HtmlHelpers 
{ 
    public static class HtmlSanitizeHelpers 
    { 
     private static readonly IDictionary<string, string[]> Whitelist; 
     private static List<string> DeletableNodesXpath = new List<string>(); 

     static HtmlSanitizeHelpers() 
     { 
      Whitelist = new Dictionary<string, string[]> { 
       { "a", new[] { "href" } }, 
       { "strong", null }, 
       { "em", null }, 
       { "blockquote", null }, 
       { "b", null}, 
       { "p", null}, 
       { "ul", null}, 
       { "ol", null}, 
       { "li", null}, 
       { "div", new[] { "align" } }, 
       { "strike", null}, 
       { "u", null},     
       { "sub", null}, 
       { "sup", null}, 
       { "table", null }, 
       { "tr", null }, 
       { "td", null }, 
       { "th", null } 
       }; 
     } 

     public static MvcHtmlString Sanitize(string input) 
     { 
      if (input.Trim().Length < 1) 
       return MvcHtmlString.Empty; 
      var htmlDocument = new HtmlDocument(); 

      htmlDocument.LoadHtml(input);    
      SanitizeNode(htmlDocument.DocumentNode); 
      string xPath = HtmlSanitizeHelpers.CreateXPath(); 

      return MvcHtmlString.Create(StripHtml(htmlDocument.DocumentNode.WriteTo().Trim(), xPath)); 
     } 

     private static void SanitizeChildren(HtmlNode parentNode) 
     { 
      for (int i = parentNode.ChildNodes.Count - 1; i >= 0; i--) 
      { 
       SanitizeNode(parentNode.ChildNodes[i]); 
      } 
     } 

     private static void SanitizeNode(HtmlNode node) 
     { 
      if (node.NodeType == HtmlNodeType.Element) 
      { 
       if (!Whitelist.ContainsKey(node.Name)) 
       { 
        if (!DeletableNodesXpath.Contains(node.Name)) 
        {      
         //DeletableNodesXpath.Add(node.Name.Replace("?","")); 
         node.Name = "removeableNode"; 
         DeletableNodesXpath.Add(node.Name); 
        } 
        if (node.HasChildNodes) 
        { 
         SanitizeChildren(node); 
        }     

        return; 
       } 

       if (node.HasAttributes) 
       { 
        for (int i = node.Attributes.Count - 1; i >= 0; i--) 
        { 
         HtmlAttribute currentAttribute = node.Attributes[i]; 
         string[] allowedAttributes = Whitelist[node.Name]; 
         if (allowedAttributes != null) 
         { 
          if (!allowedAttributes.Contains(currentAttribute.Name)) 
          { 
           node.Attributes.Remove(currentAttribute); 
          } 
         } 
         else 
         { 
          node.Attributes.Remove(currentAttribute); 
         } 
        } 
       } 
      } 

      if (node.HasChildNodes) 
      { 
       SanitizeChildren(node); 
      } 
     } 

     private static string StripHtml(string html, string xPath) 
     { 
      HtmlDocument htmlDoc = new HtmlDocument(); 
      htmlDoc.LoadHtml(html); 
      if (xPath.Length > 0) 
      { 
       HtmlNodeCollection invalidNodes = htmlDoc.DocumentNode.SelectNodes(@xPath); 
       foreach (HtmlNode node in invalidNodes) 
       { 
        node.ParentNode.RemoveChild(node, true); 
       } 
      } 
      return htmlDoc.DocumentNode.WriteContentTo(); ; 
     } 

     private static string CreateXPath() 
     { 
      string _xPath = string.Empty; 
      for (int i = 0; i < DeletableNodesXpath.Count; i++) 
      { 
       if (i != DeletableNodesXpath.Count - 1) 
       { 
        _xPath += string.Format("//{0}|", DeletableNodesXpath[i].ToString()); 
       } 
       else _xPath += string.Format("//{0}", DeletableNodesXpath[i].ToString()); 
      } 
      return _xPath; 
     } 
    } 
} 

學分大多數代碼去在this posting答案。

事情我已經檢查：

1. 命名空間已在Web.config文件中已經正確定義。 （我也知道這是因爲命名空間中的其他人已經工作）
2. 已經完成了項目的清理構建。
3. 重新啓動的Visual Studio 2010中

爲什麼我似乎無法調用從類方法的思考？

Answer 1

看起來您並沒有正確地擴展HtmlHelper。

你缺少你的函數定義如下：

public static MvcHtmlString Sanitize(this HtmlHelper helper, string input) 

檢查出Using Class Extensions to simplify your code with the UrlHelper