C#去除HTML,Javascript等标签通用类
发布时间：2009年10月13日点击数：
次未知
using ...System;
using System.Text;
using System.Text.RegularExpressions;
namespace Onfly.Common
...{
///
/// 过滤类
///
public class Filter
...{
///
/// 需要过滤的字符（多个以|相隔）
///
public static string _keyWord = "";
///
/// 需要过滤的字符（多个以|相隔）
///
public static string KeyWord
...{
get ...{ return _keyWord; }
set ...{ _keyWord = value; }
}
///
/// 过滤 Javascript
///
///
"content">
///
public static string FilterScript(string content)
...{
string commentPattern = @"(?'comment')";
string embeddedScriptComments = @"(\/\*.*?\*\/|\/\/.*?[\n\r])";
string scriptPattern = String.Format(@"(?'script']*>(.*?...{0}?)*]*>)", embeddedScriptComments);
string pattern = String.Format(@"(?s)(...{0}|{1})", commentPattern, scriptPattern);
return StripScriptAttributesFromTags(Regex.Replace(content, pattern, string.Empty, RegexOptions.IgnoreCase));
}
///
/// 过滤javascript属性值（如onclick等）
///
///
"content">
///
private static string StripScriptAttributesFromTags(string content)
...{
string eventAttribs = @"on(blur|c(hange|lick)|dblclick|focus|keypress|(key|mouse)(down|up)|(un)?load
|mouse(move|o(ut|ver))|reset|s(elect|ubmit))";
string pattern = String.Format(@"(?inx)
\<(\w+)\s+
(
(?'attribute'
(?'attributeName'...{0})\s*=\s*
(?'delim'['""]?)
(?'attributeValue'[^'"">]+)
(\3)
)
|
(?'attribute'
(?'attributeName'href)\s*=\s*
(?'delim'['""]?)
(?'attributeValue'javascript[^'"">]+)
(\3)
)
|
[^>]
)*
\>", eventAttribs);
Regex re = new Regex(pattern);
// 使用MatchEvaluator的委托
return re.Replace(content, new MatchEvaluator(StripAttributesHandler));
}
///
/// 取得属性值
///
///
"m">
///
private static string StripAttributesHandler(Match m)
...{
if (m.Groups["attribute"].Success)
...{
return m.Value.Replace(m.Groups["attribute"].Value, "");
}
else
...{
return m.Value;
}
}
///
/// 去掉javascript（scr链接方式）
///
///
"content">
///
public static string FilterAHrefScript(string content)
...{
string newstr = FilterScript(content);
string regexstr = @" href[ ^=]*= *[\s\S]*script *:";
return Regex.Replace(newstr, regexstr, string.Empty, RegexOptions.IgnoreCase);
}
///
/// 去掉链接文件
///
///
"content">
///
public static string FilterSrc(string content)
...{
string newstr = FilterScript(content);
string regexstr = @" src *= *['""]?[^\.]+\.(js|vbs|asp|aspx|php|jsp)['""]";
return Regex.Replace(newstr, regexstr, @"", RegexOptions.IgnoreCase);
}
///
/// 过滤HTML
///
///
"content">
///
public static string FilterHtml(string content)
...{
string newstr = FilterScript(content);
string regexstr = @"]*>";
return Regex.Replace(newstr, regexstr, string.Empty, RegexOptions.IgnoreCase);
}
///
/// 过滤 OBJECT
///
///
"content">
///
public static string FilterObject(string content)
...{
string regexstr = @"(?i)])*>(\w|\W)*])*>";
return Regex.Replace(content, regexstr, string.Empty, RegexOptions.IgnoreCase);
}
///
/// 过滤iframe
///
///
"content">
///
public static string FilterIframe(string content)
...{
string regexstr = @"(?i)])*>(\w|\W)*])*>";
return Regex.Replace(content, regexstr, string.Empty, RegexOptions.IgnoreCase);
}
///
/// 过滤frameset
///
///
"content">
///
public static string FilterFrameset(string content)
...{
string regexstr = @"(?i)])*>(\w|\W)*])*>";
return Regex.Replace(content, regexstr, string.Empty, RegexOptions.IgnoreCase);
}
///
/// 移除非法或不友好字符
///
///
"chkStr">
///
public static string FilterBadWords(string chkStr)
...{
//这里的非法和不友好字符由你任意加，用“|”分隔，支持正则表达式,由于本Blog禁止贴非法和不友好字符，所以这里无法加上。
if (chkStr == "")
...{
return "";
}
string[] bwords = _keyWord.Split('|');
int i, j;
string str;
StringBuilder sb = new StringBuilder();
for (i = 0; i < bwords.Length; i++)
...{
str = bwords[i].ToString().Trim();
string regStr, toStr;
regStr = str;
Regex r = new Regex(regStr, RegexOptions.IgnoreCase | RegexOptions.Singleline | RegexOptions.Multiline);
Match m = r.Match(chkStr);
if (m.Success)
...{
j = m.Value.Length;
sb.Insert(0, "*", j);
toStr = sb.ToString();
chkStr = Regex.Replace(chkStr, regStr, toStr, RegexOptions.IgnoreCase | RegexOptions.Singleline | RegexOptions.Multiline);
}
sb.Remove(0, sb.Length);
}
return chkStr;
}
///
/// 过滤以上所有
///
///
"content">
///
public static string FilterAll(string content)
...{
content = FilterHtml(content);
content = FilterScript(content);
content = FilterAHrefScript(content);
content = FilterObject(content);
content = FilterIframe(content);
content = FilterFrameset(content);
content = FilterSrc(content);
content = FilterBadWords(content);
return content;
}
}
}
