md文档生成目录(Toc)

gistfile1.js

  <style type="text/css">
  #toc ul {margin: 0}
  #toc>ul {padding:0}
  li.decimal {list-style-type: decimal;}
  li.lroman {list-style-type: lower-roman;}
  li.lalpha {list-style-type: lower-alpha;}
  li,li.square {list-style-type: square}  
  </style>
<script>
window.onload = function () {
  var toc = "";
    var level = 0;

      document.getElementsByTagName("body")[0].innerHTML =
          document.getElementsByTagName("body")[0].innerHTML.replace(
              /<h([2-5])>([^<]+)<\/h([\d])>/gi,
              function (str, openLevel, titleText, closeLevel) {
                  if (openLevel != closeLevel) {
                      return str;
                  }

                  if (openLevel > level) {
                      toc += (new Array(openLevel - level + 1)).join("<ul>");
                  } else if (openLevel < level) {
                      toc += (new Array(level - openLevel + 1)).join("</ul>");
                  }

                  level = parseInt(openLevel);

                  var anchor = titleText.replace(/ /g, "_");
                  var classname = '';
                  switch(level)
                  {
                    case 2:
                      classname = 'decimal';
                      break;
                    case 3:
                      classname = 'lroman';
                      break;
                    case 4:
                      classname = 'lalpha';
                      break;
                    
                      
                  }
                  toc += "<li class='"+classname+"'><a href=\"#" + anchor + "\">" + titleText
                      + "</a></li>";

                  return "<h" + openLevel + "><a name=\"" + anchor + "\">"
                      + titleText + "</a></h" + closeLevel + ">";
              }
          );


	if (level) {
		toc += (new Array(level + 1)).join("</ul>");
	}

	document.getElementById("toc").innerHTML += toc;
};
	</script>
 <div id="toc">
<h1>目录</h1>
 </div>