介绍了javascript的常用的函数

				 
				  
				  
				  JavaScript Book--代码6-20
				  
				  
				  				  var elementName = "";
				  function countTotalElement(node){
				  var total = 0;
				  if(node.nodeType == 1){
				  total ++;
				  elementName = elementName + node.tagName + "\r\n";
				  }
				
				  var childrens = node.childNodes;
				  for(var i = 0 ; i < childrens.length; i++){
				  total += countTotalElement(childrens[i]);
				  }
				
				  return total;
				  }
				
				  function count(){
				  var all = '标签总数:' + countTotalElement(document) + '\r\n标签列表如下： \r\n' + elementName;
				  alert(all);
				  }
				  -->