C#正则实现Ubb解析类的代码

C#正则实现Ubb解析类的代码

作者： 字体：[增加 减小] 类型：转载 时间：2007-03-30

 

 

解析得到的代码能通过XHTML 1.0 STRICT验证; 
包含了标题,链接,字体,对齐,图片,引用,列表等方面的功能.  

代码如下:

//作者:deerchao  
// http://www.unibetter.com/blogs/blogdeerchao/default.aspx  
//在不移除以上(及本条)注释的前提下,任何人可以以任何方式使用此代码.  

using System;  
using System.Collections.Generic;  
using System.Text;  
using System.Web;  
using System.Text.RegularExpressions;  

namespace Deerchao.Web  
{  
    public class UbbDecoder  
    {  
        private static readonly RegexOptions options = RegexOptions.Compiled | RegexOptions.Singleline; 

        /// <summary>  
        /// 解析Ubb代码为Html代码  
        /// </summary>  
        /// <param name="ubb">Ubb代码</param>  
        /// <returns>解析得到的Html代码</returns>  
        public static string Decode(string ubb)  
        {  
            if (string.IsNullOrEmpty(ubb))  
                return null;  
            string result = ubb;  
            result = HttpUtility.HtmlEncode(result);  

            result = DecodeStyle(result);  
            result = DecodeFont(result);  
            result = DecodeColor(result);  
            result = DecodeImage(result);  
            result = DecodeLinks(result);  
            result = DecodeQuote(result);  
            result = DecodeAlign(result);  
            result = DecodeList(result);  
            result = DecodeHeading(result);  
            result = DecodeBlank(result);  

            return result;  
        }  

        /// <summary>  
        /// 解析Ubb代码为Html代码,所有的链接为rel="nofollow"  
        /// </summary>  
        /// <param name="ubb">Ubb代码</param>  
        /// <returns>解析得到的Html代码</returns>  
        public static string DecodeNoFollow(string ubb)  
        {  
            if (string.IsNullOrEmpty(ubb))  
                return null;  
            string result = ubb;  
            result = HttpUtility.HtmlEncode(result);  

            result = DecodeStyle(result);  
            result = DecodeFont(result);  
            result = DecodeColor(result);  
            result = DecodeImage(result);  
            result = DecodeLinksNoFollow(result);  
            result = DecodeQuote(result);  
            result = DecodeAlign(result);  
            result = DecodeList(result);  
            result = DecodeHeading(result);  
            result = DecodeBlank(result);  

            return result;  
        }  

        private static string DecodeHeading(string ubb)  
        {  
            string result = ubb;  
            result = Regex.Replace(result, @"\[h(\d)\](.*?)\[/h\1\]", "<h$1>$2</h$1>", options);  
            return result;  
        }  

        private static string DecodeList(string ubb)  
        {  
            string sListFormat = "<ol style=\"list-style:{0};\">$1</ol>";  
            string result = ubb;  
            // Lists  
            result = Regex.Replace(result, @"\[\*\]([^\[]*)", "<li>$1</li>", options);  
            result = Regex.Replace(result, @"\[list\]\s*(.*?)\[/list\]", "<ul>$1</ul>", options);  
            result = Regex.Replace(result, @"\[list=1\]\s*(.*?)\[/list\]", string.Format(sListFormat, "decimal"), options);  
            result = Regex.Replace(result, @"\[list=i\]\s*(.*?)\[/list\]", string.Format(sListFormat, "lower-roman"), options);  
            result = Regex.Replace(result, @"\[list=I\]\s*(.*?)\[/list\]", string.Format(sListFormat, "upper-roman"), options);  
            result = Regex.Replace(result, @"\[list=a\]\s*(.*?)\[/list\]", string.Format(sListFormat, "lower-alpha"), options);  
            result = Regex.Replace(result, @"\[list=A\]\s*(.*?)\[/list\]", string.Format(sListFormat, "upper-alpha"), options);  

            return result;  
        }  

        private static string DecodeBlank(string ubb)  
        {  
            string result = ubb;  

            result = Regex.Replace(result, @"(?<= ) | (?= )", " ", options);  
            result = Regex.Replace(result, @"\r\n", "<br />");  
            string[] blockTags = {"h[1-6]", "li", "list", "div", "p", "ul"};  
            //clear br before block tags(start or end)  
            foreach (string tag in blockTags)  
            {  
                Regex r = new Regex("<br />(<" + tag + ")",options);  
                result = r.Replace(result, "$1");  
                r = new Regex("<br />(</" + tag + ")",options);  
                result = r.Replace(result, "$1");  
            }  
            return result;  
        }  

        private static string DecodeAlign(string ubb)  
        {  
            string result = ubb;  

            result = Regex.Replace(result, @"\[left\](.*?)\[/left\]", "<div style=\"text-align:left\">$1</div>", options);  
            result = Regex.Replace(result, @"\[right\](.*?)\[/right\]", "<div style=\"text-align:right\">$1</div>", options);  
            result = Regex.Replace(result, @"\[center\](.*?)\[/center\]", "<div style=\"text-align:center\">$1</div>", options);  

            return result;  
        }  

        private static string DecodeQuote(string ubb)  
        {  
            string result = ubb;  

            result = Regex.Replace(result, @"\[quote\]", "<blockquote><div>", options);  
            result = Regex.Replace(result, @"\[/quote\]", "</div></blockquote>", options);  
            return result;  
        }  

        private static string DecodeFont(string ubb)  
        {  
            string result = ubb;  

            result = Regex.Replace(result, @"\[size=([-\w]+)\](.*?)\[/size\]", "<span style=\"font-size:$1\">$2</span>", options);  
            result = Regex.Replace(result, @"\[font=(.*?)\](.*?)\[/font\]", "<span style=\"font-family:$1\">$2</span>", options);  
            return result;  
        }  

        private static string DecodeLinks(string ubb)  
        {  
            string result = ubb;  

            result = Regex.Replace(result, @"\[url\]www\.(.*?)\[/url\]", "<a href=\"http://www.$1\">$1</a>", options);  
            result = Regex.Replace(result, @"\[url\](.*?)\[/url\]", "<a href=\"$1\">$1</a>", options);  
            result = Regex.Replace(result, @"\[url=(.*?)\](.*?)\[/url\]", "<a href=\"$1\" title=\"$2\">$2</a>", options);  
            result = Regex.Replace(result, @"\[email\](.*?)\[/email\]", "<a href=\"mailto:$1\">$1</a>", options);  
            return result;  
        }  

        private static string DecodeLinksNoFollow(string ubb)  
        {  
            string result = ubb;  

            result = Regex.Replace(result, @"\[url\]www\.(.*?)\[/url\]", "<a rel=\"nofollow\" href=\"http://www.$1\">$1</a>", options);  
            result = Regex.Replace(result, @"\[url\](.*?)\[/url\]", "<a rel=\"nofollow\" href=\"$1\">$1</a>", options);  
            result = Regex.Replace(result, @"\[url=(.*?)\](.*?)\[/url\]", "<a rel=\"nofollow\" href=\"$1\" title=\"$2\">$2</a>", options);  
            result = Regex.Replace(result, @"\[email\](.*?)\[/email\]", "<a href=\"mailto:$1\">$1</a>", options);  
            return result;  
        }  

        private static string DecodeImage(string ubb)  
        {  
            string result = ubb;  

            result = Regex.Replace(result, @"\[hr\]", "<hr />", options);  
            result = Regex.Replace(result, @"\[img\](.+?)\[/img\]", "<img src=\"$1\" alt=\"\" />", options); 
            result = Regex.Replace(result, @"\[img=(\d+)x(\d+)\](.+?)\[/img\]", "<img src=\"$3\" style=\"width:$1px;height:$2px\" alt=\"\" />", options);  

            return result;  
        }  

        private static string DecodeColor(string ubb)  
        {  
            string result = ubb;  
            result = Regex.Replace(result, @"\[color=(#?\w+?)\](.+?)\[/color\]", "<span style=\"color:$1\">$2</span>",options);  

            return result;  
        }  

        private static string DecodeStyle(string ubb)  
        {  
            string result=ubb;  
            //we don't need this for perfomance and other consideration:  
            //(<table[^>]*>(?><table[^>]*>(?<Depth>)|</table>(?<-Depth>)|.)+(?(Depth)(?!))</table>)  
            result = Regex.Replace(result, @"\[[b]\](.*?)\[/[b]\]", "<strong>$1</strong>", options);  
            result = Regex.Replace(result, @"\[[u]\](.*?)\[/[u]\]", "<span style=\"text-decoration:underline\">$1</span>", options);  
            result = Regex.Replace(result, @"\[[i]\](.*?)\[/[i]\]", "<i>$1</i>", options);  

            return result;  
        }  
    }  
} 

 

来源： http://www.jb51.net/article/9009.htm