原生javascript

在线实例：http://www.lgyweb.com/tab/

分析个人用原生JS获取类名元素的代码：

getByClassName:function(className,parent){
            var elem = [],
                node = parent != undefined&&parent.nodeType==1?parent.getElementsByTagName('*'):document.body.getElementsByTagName('*'),
                p = new RegExp("(^|\\s)"+className+"(\\s|$)");
            for(var n=0,i=node.length;n<i;n++){
                if(p.test(node[n].className)){
                    elem.push(node[n]);
                }
            }
            return elem;
        }

parent参数是可选的，但需要先判断它是否存在，且是节点dom元素 parent != undefined&&parent.nodeType==1 ，nodeType == 1可以判断节点是否为dom元素，在火狐浏览器里面，空白也算是节点（.childnodes），用这个属性就判断是否为dom元素，排除空白符.

 

移除元素的类名：

 

var cur = new RegExp(this.sCur,'g');  //this.sCur就是类名，这里是用变量保存 如：this.sCur = "cur";
           this.oTab_btn[n].className = this.oTab_btn[n].className.replace(cur,'');         

 

以下为详细代码：

function LGY_tab(option){
        this.oTab_btn = this.getDom(option.tabBtn);//切换点击的元素
        this.oTab_clist = this.getDom(option.tabCon); //切换的内容
        this.sCur = option.cur; //激活的状态
        this.type = option.type || 'click';
        this.nLen = this.oTab_btn.length;
        this.int();
    }
    LGY_tab.prototype = {
        getId:function(id){
            return document.getElementById(id);
        },
        getByClassName:function(className,parent){
            var elem = [],
                node = parent != undefined&&parent.nodeType==1?parent.getElementsByTagName('*'):document.body.getElementsByTagName('*'),
                p = new RegExp("(^|\\s)"+className+"(\\s|$)");
            for(var n=0,i=node.length;n<i;n++){
                if(p.test(node[n].className)){
                    elem.push(node[n]);
                }
            }
            return elem;
        },
        getDom:function(s){
            var nodeName = s.split(' '),
                p = this.getId(nodeName[0].slice(1)),
                c = this.getByClassName(nodeName[1].slice(1),p);
            return c;
        },
        change:function(){
            var cur = new RegExp(this.sCur,'g');
            for(var n=0;n<this.nLen;n++){
                this.oTab_clist[n].style.display = 'none';
                this.oTab_btn[n].className = this.oTab_btn[n].className.replace(cur,'');
            }
        },
        int:function(){
            var that = this;
            this.oTab_btn[0].className += ' '+this.sCur;
            this.oTab_clist[0].style.display = 'block';
            for(var n=0;n<this.nLen;n++){
                this.oTab_btn[n].index = n;
                this.oTab_btn[n]['on'+this.type] = function(){
                    that.change();
                    that.oTab_btn[this.index].className +=' ' + that.sCur;
                    that.oTab_clist[this.index].style.display = 'block';
                }
            }
        }
    }