asp.net 过滤网页特殊字符串

字符串过滤类 FilterStrFactoryHandler

 1 using System;
 2 using System.IO;
 3 using System.Web.UI;
 4 using System.Web;
 5 using System.Configuration;
 6 using System.Text.RegularExpressions;
 7 using System.Web.Compilation;
 8 using System.Reflection;
 9 using System.Collections.Specialized;
10 using System.Web.UI.WebControls;
11 using System.Web.UI.HtmlControls;
12 
13 namespace JY.Utils
14 {
15     /// <summary>
16     ///FilterStrFactoryHandler 的摘要说明
17     /// </summary>
18     public class FilterStrFactoryHandler : IHttpHandlerFactory
19     {
20         public virtual IHttpHandler GetHandler(HttpContext context, string requestType, string url, 
　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　string pathTranslated)
21         {
22             //得到编译实例(通过反射)
23             PageHandlerFactory factory = 
　　　　　　　　　　　　　　　　(PageHandlerFactory)Activator.CreateInstance(typeof(PageHandlerFactory), true);
24             IHttpHandler handler = 
　　　　　　　　　　　　　　　　factory.GetHandler(context, requestType, url, pathTranslated);
25             //过滤字符串
26             if (requestType == "POST")
27             {
28                 Page page = handler as Page;
29                 if (page != null)
30                     page.PreLoad += new EventHandler(FilterStrFactoryHandler_PreLoad);
31             }
32             //返回
33             return handler;
34         }
35 
36         //过滤TextBox、Input和Textarea中的特殊字符
37         void FilterStrFactoryHandler_PreLoad(object sender, EventArgs e)
38         {
39             try
40             {
41                 Page page = sender as Page;
42                 NameValueCollection postData = page.Request.Form;
43                 foreach (string postKey in postData)
44                 {
45                     Control ctl = page.FindControl(postKey);
46                     if (ctl as TextBox != null)
47                     {
48                         ((TextBox)ctl).Text = InputText(((TextBox)ctl).Text);
49                         continue;
50                     }
51                     if (ctl as HtmlInputControl != null)
52                     {
53                         ((HtmlInputControl)ctl).Value = InputText(((HtmlInputControl)ctl).Value);
54                         continue;
55                     }
56                     if (ctl as HtmlTextArea != null)
57                     {
58                         ((HtmlTextArea)ctl).Value = InputText(((HtmlTextArea)ctl).Value);
59                         continue;
60                     }
61                 }
62             }
63             catch { }
64         }
65 
66         public virtual void ReleaseHandler(IHttpHandler handler)
67         {
68         }
69 
70         //字符串过滤
71         public static string InputText(string text)
72         {
73             text = text.Trim();
74             if (string.IsNullOrEmpty(text))
75                 return string.Empty;
76             text = Regex.Replace(text, "[\\s]{2,}", "");    //two or more spaces
77             text = Regex.Replace(text, "(<[b|B][r|R]/*>)+|(<[p|P](.|\\n)*?>)", "\n");    //<br>
78             text = Regex.Replace(text, "(\\s*&[n|N][b|B][s|S][p|P];\\s*)+", " ");    //&nbsp;
79             text = Regex.Replace(text, "<(.|\\n)*?>", string.Empty);    //any other tags
80             text = text.Replace("'", "");
81             text = text.Replace("%", "");
82             //text = text.Replace("_", "");
83             return text;
84         }
85     }
86 }

web.config配置

<httpHandlers>
      <!--过滤提交给服务器的文本信息-->
     <add verb="*" path="*.aspx" validate="false" type="JY.Utils.FilterStrFactoryHandler, JY.Utils"/>
</httpHandlers>
posted @ 2011-04-26 13:29  xunslei  阅读(1201)  评论(1)    收藏  举报