事件委托 兼容性写法

var ul = document.getElementById("ul")
    var json = [{"a":"1","b":"2","c":"3"},{"a":"2","b":"2","c":"3"},{"a":"3","b":"2","c":"3"}]
    // $.each(json,function (index,item) {
    //     var li = '<li>'+item.a+'</li>'
    //     $("ul").append(li)
    // })
    for(i = 0;i<json.length;i++){
        var lis = '<li>'+json[i].a+'</li>'
        $("ul").append(lis)
    }
    var addEvent = function(element,type,callback){
        if(element.addEventListener){
            element.addEventListener(type,callback,false);
        }else if(element.attachEvent){
            element.attachEvent('on' + type,callback)
        }

    }

    addEvent(document.getElementById('ul'), 'click', function (event) {
        var event = event || window.event;
        var target = event.target || event.srcElement;
        if (target.nodeName.toLowerCase() == 'li') {
            console.log(target.innerHTML)
        }