JavaScript链式编程模拟Jquery函数

 1 <span>Hello,World！</span>
 2 <script type="text/javascript">
 3     Jq = function (tagName) {
 4         var tagArr = document.getElementsByTagName(tagName);
 5         var ret = {
 6             tag: tagArr,
 7             css: function (attribute, value) {
 8                 for (var i = 0; i < this.tag.length; i++) {
 9                     this.tag[i].style[attribute] = value;
10                 }
11                 return this;
12             }
13         }
14         return ret;
15     }
16 
17     window.onload = function () {
18         Jq("span").css("color", "red")
19                   .css("border", "1px solid green")
20                   .css("padding", "10px");
21     }
22 </script>