浏览器再getTarget该方法显示Unexpected identifier

/*声明全局变量*/

var index = 0,// 当前显示图片的索引

    prev = byId("prev"), 

    next = byId("next");

// 封装getElemntById()

function byId(id){

if(typeof(id) ==="string"){

return document.getElementById(id);

}else {return id;}

}

//封装通用事件绑定事件

// 参数1:elemnt绑定事件的DOM元素

//  参数2:事件名

//    参数3：事件处理程序

var EventUtil = {

addHandler: function(element, type, handler) {

if (element.addEventListener) {

element.addEventListener(type, handler, true);

} else if (element.addattachEvent) {

element.addattachEvent("on" + type, handler);

} else {

element["on" + type] = handler;

}

},

removeHandler: function(element, type, handler) {

if (element.addEventListener) {

element.addEventListener(type, handler, true);

} else if (element.addattachEvent) {

element.addattachEvent("on" + type, handler);

} else {

element["on" + type] = null;

}

},

跨浏览器事件对象的兼容性处理

getTarget: function(event) {

return event.target || event.srcElement;

},

preventDefault: function(event) {

if (event.preventDefault) {

event.preventDefault();

} else {

event.returValue = false;

}

},

stopPropagation: function(event) {

if (event.stopPropagation) {

event.stopPropagation();

} else {

event.cancelBubble = true;

}

}

};

//点击下一张按钮，显示下一张图片

//DOM0级事件

prev.addEventListener("click",function(){

alert("1");

});

next.addEventListener("click",function(){

alert("2");

});

如上所示