js工具函数

1.等待所有图片加载

var imgObjs = [],
　　 count = 0;
rotate.prizeTotal = prizes.length;//图片总数
var timer = setInterval(function() {

    if (count == rotate.prizeTotal ) {
        clearInterval(timer);                    
    	//加载后执行的回调函数
    }
}, 50);
for(var i = 0;i < prizes.length; i++){
	var img = new Image();
	img.src = prizes[i].prize_icon;	//prizes数组的prize_icon存放图片的地址
	imgObjs.push(img);	
	img.onload = function(){
		count++;		
	}

}