代码记录(一)

window.onload = function(){
    var xia = document.getElementById('xia');
    var shang = document.getElementById('shang');
    var html = document.getElementById('html');
        xia.onclick = function(){
            slids.ent();
        }
        shang.onclick = function(){
            slids.enet();
        }
}
var slids = {
    title:["男子跑步","女子跑步","男子足球","女子足球","男子篮球","女子篮球","男子网球","女子网球","男子羽毛球","女子羽毛球","男子自行车"],
    index:0,
    ent:function(){
        var _this = this;
        _this.index++;
        _this.index = _this.index>=_this.title.length-1?_this.title.length-1:_this.index;
        //    alert(_this.index);
        html.innerHTML = _this.title[_this.index];
        return false;
    },
    enet : function(){
        var _this = this;
        _this.index--;
        _this.index = _this.index<=0?0:_this.index;
        //    alert(_this.index);
        html.innerHTML = _this.title[_this.index];
        return false;
    }
}