|
@@ -19,6 +19,66 @@
|
|
//获取屏幕的宽高
|
|
//获取屏幕的宽高
|
|
var screenWidth = document.body.clientWidth || document.documentElement.clientWidth;
|
|
var screenWidth = document.body.clientWidth || document.documentElement.clientWidth;
|
|
var screenHeight = document.body.clientHeight || document.documentElement.clientHeight;
|
|
var screenHeight = document.body.clientHeight || document.documentElement.clientHeight;
|
|
|
|
+ //构造函数 写属性
|
|
|
|
+ function leaf() {
|
|
|
|
+ //图片宽度
|
|
|
|
+ this.width = Math.random() * 100 + 100;
|
|
|
|
+ //图片距离左边的距离
|
|
|
|
+ this.xLeft = Math.random() * (screenWidth - this.width)
|
|
|
|
+ //距离顶部
|
|
|
|
+ this.xTop = 0
|
|
|
|
+ //图片路径
|
|
|
|
+ this.bg = 'img/' + Math.floor(Math.random() * 4 + 1) + '.png'
|
|
|
|
+ /*
|
|
|
|
+ 如何让随机数为1,2,3,4整数
|
|
|
|
+ Math.random() 0-1随机小数
|
|
|
|
+ Math.random() * 4 0-4随机小数
|
|
|
|
+ Math.random() * 4 + 1 1-5之间的随机小数 不包括5
|
|
|
|
+
|
|
|
|
+ Math.floor() 向下取整 跟四舍五入没关系
|
|
|
|
+ Math.floor(Math.random() * 4 + 1) 1,2,3,4
|
|
|
|
+ */
|
|
|
|
+ }
|
|
|
|
+ // 原型下面写方法
|
|
|
|
+ leaf.prototype.init = function(){
|
|
|
|
+ //创建img标签
|
|
|
|
+ var oImg = document.createElement('img')
|
|
|
|
+ //引用路径
|
|
|
|
+ oImg.src = this.bg
|
|
|
|
+ oImg.style.width = this.width + 'px'
|
|
|
|
+ oImg.style.left = this.xLeft + 'px'
|
|
|
|
+ oImg.style.top = this.xTop + 'px'
|
|
|
|
+ this.img = oImg
|
|
|
|
+ document.body.appendChild(oImg)
|
|
|
|
+ }
|
|
|
|
+ //下落的方法
|
|
|
|
+ leaf.prototype.fall = function(){
|
|
|
|
+ //叶子起始延迟时间
|
|
|
|
+ setTimeout(function(){
|
|
|
|
+ this.timer = setInterval(function(){
|
|
|
|
+ console.log(this)
|
|
|
|
+ if(this.img.offsetTop < screenHeight - this.img.offsetHeight){
|
|
|
|
+ this.img.style.top = this.img.offsetTop + 10 + 'px'
|
|
|
|
+ } else {
|
|
|
|
+ clearInterval(this.timer)
|
|
|
|
+ }
|
|
|
|
+ }.bind(this),20)
|
|
|
|
+ // console.log(this)
|
|
|
|
+ }.bind(this),Math.random()*2000)
|
|
|
|
+ // console.log(this)
|
|
|
|
+ }
|
|
|
|
+ var leafArr = []
|
|
|
|
+ for (var i = 0; i < 20; i++) {
|
|
|
|
+ //创建实例化对象
|
|
|
|
+ var leaf1 = new leaf()
|
|
|
|
+ leafArr.push(leaf1)
|
|
|
|
+ leaf1.init()
|
|
|
|
+ }
|
|
|
|
+ document.onclick = function(){
|
|
|
|
+ for(var i=0;i<leafArr.length;i++){
|
|
|
|
+ leafArr[i].fall()
|
|
|
|
+ }
|
|
|
|
+ }
|
|
</script>
|
|
</script>
|
|
</body>
|
|
</body>
|
|
|
|
|