模板引擎開發(fā)（三）-自定義標(biāo)簽的處理

  <Tag Uid="5895643">
      <Name>PageTop</Name>
      <Type>page</Type>
      <Intro><![CDATA[所有頁面的頂部]]></Intro>
      <Page>PageTop.html</Page>
      <Context><![CDATA[<div id="pagetop">logo 信息化動(dòng)力核心 </div>
<div></div>]]></Context>
    </Tag>

/// <summary>
        /// 將模板內(nèi)容中的所有自定義標(biāo)簽，替換為實(shí)際的值
        /// </summary>
        /// <param name="html">要處理的模板對(duì)象</param>
        /// <returns></returns>
        public string Transact(TemplateBuider.PageTransact.Html html)
        {
            string patt = @"{%@\s*(\S[^\s%]+)\s*%}";
            Regex rex = new Regex(patt, RegexOptions.Singleline);
            MatchCollection mc = rex.Matches(html.HtmlContext);
            for (int i = 0; i < mc.Count; i++)
            {
                Match ma = mc[i];
                string key = ma.Groups[1].Value;
                //獲取當(dāng)前標(biāo)簽對(duì)象
                Song.TemplateManager.Tags.CustomTag custom = _tags.Find(delegate(TemplateManager.Tags.CustomTag p) { return p.Name.ToLower() == key.ToLower(); });
                if (custom == null) continue;
                //轉(zhuǎn)換自定義標(biāo)簽中的路徑，使之與當(dāng)前模板頁為相對(duì)路徑
                string context =_replacePath(html, custom);
                //將自定義標(biāo)簽合并到的模板
                html.HtmlContext = Microsoft.VisualBasic.Strings.Replace(html.HtmlContext, ma.Value, context, 1, -1, Microsoft.VisualBasic.CompareMethod.Text);
            }
            return html.HtmlContext;
        }

       /// <summary>
        /// 計(jì)算兩個(gè)文件的相對(duì)路徑
        /// </summary>
        /// <param name="baseFile">用于參照的文件，就從當(dāng)前文件開始查找另一個(gè)文件</param>
        /// <param name="targetFile">目標(biāo)文件，就是求它的相對(duì)路徑</param>
        /// <returns>返回targetFile相對(duì)于baseFile的相對(duì)路徑</returns>
        private string _getRelativePath(string baseFile, string targetFile)
        {
            baseFile = baseFile.Replace("\\", "/");
            baseFile = baseFile.ToLower();
            targetFile = targetFile.ToLower();
            //
            while (baseFile.IndexOf("/") > -1 && targetFile.IndexOf("/") > -1)
            {
                string b = baseFile.Substring(0, baseFile.IndexOf("/"));
                string t = targetFile.Substring(0, targetFile.IndexOf("/"));
                if (b != t) break;                
                baseFile = baseFile.Substring(baseFile.IndexOf("/") + 1);
                targetFile = targetFile.Substring(targetFile.IndexOf("/") + 1);               
            }
            string path = "";
            while (baseFile.IndexOf("/") > -1)
            {
                baseFile = baseFile.Substring(baseFile.IndexOf("/") + 1);
                path += "../";
            }
            return path + targetFile;
        }

        /// <summary>
        /// 將模板頁中的路徑處理成相對(duì)于當(dāng)前模板頁的路徑
        /// </summary>
        /// <param name="html"></param>
        /// <param name="tag"></param>
        /// <returns></returns>
        private string _replacePath(TemplateBuider.PageTransact.Html html, TemplateManager.Tags.CustomTag tag)
        {
            string context = tag.Context;
            //處理自定義標(biāo)簽中的超鏈接，使其相對(duì)于當(dāng)前文件路徑            
            string cutomPath = _cutomPath(tag);
            //將超鏈接處理為相對(duì)于模板頁的路徑
            string linkExpr = @"(?<=\s+)(?<key>href|src|action|background[^=""']*)=([""'])?(?<value>[^'"">]*)\1?";
            Regex regex = new Regex(linkExpr, RegexOptions.Multiline | RegexOptions.IgnorePatternWhitespace | RegexOptions.IgnoreCase);
            MatchCollection mc = regex.Matches(tag.Context);
            foreach (Match m in mc)
            {
                string link = m.Groups["value"].Value.Trim();
                if (link == "") continue;
                //外網(wǎng)鏈接不處理，如Http://開頭的超鏈接
                if (new Regex(@"[a-zA-z]+://[^\s]*", RegexOptions.Singleline).IsMatch(link))
                    continue;
                //根路徑不處理，如/manage/index.aspx，第一個(gè)字符是/
                if (new Regex(@"^\/\w+.").IsMatch(link))
                    continue;
                //如果是參數(shù)標(biāo)簽，則不處理
                if (new Regex(@"^{.+").IsMatch(link))
                    continue;
                //將超鏈接轉(zhuǎn)換為相對(duì)于靜態(tài)化目錄的路徑
                link = _getCutomLinkPath(cutomPath, link);
                //將超鏈接轉(zhuǎn)換為基于當(dāng)前模板頁的相對(duì)路徑
                link = _getRelativePath(html.TagetFile, link);
                link = m.Groups[2].Value + "=\"" + link + "\"";
                context = context.Replace(m.Value, link);
            }
            return context;
        }