JavaScript 实现下雪特效的示例代码

站长资源 2024/11/25 佚名

2 0 1

直接上代码

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>下雪效果实现</title>
  <link rel="stylesheet" type="text/css" href="reset.css">
  <style type="text/css">
    body,html{
      overflow: hidden;
    }
  </style>
</head>
<body>
  <script type="text/javascript">
    var snowflakes = {
      arr:[],// 数组盛放元素
      snowflake : [//雪花类型
            '"red",
            "green",
            "#ccc123",
            "#345232",
            "#231111",
            "#ab2322"
            ],
       random : function (num){
        return Math.floor(Math.random()*num);// 获得一个num-1的整数
       },
       init : function (num){
        // 最多个数
        this.maxlength = num;
        // 边界
        this.maxWidth = (document.documentElement.clientWidth || document.body.clientWidth) + 20;
        // 边界
        this.maxHeight = (document.documentElement.clientHeight || document.body.clientHeight) + 20;
        this.create();
        this.move();
       },
       // 创建
       create : function (){
        var that = this;
        setInterval(function (){
          // 当数组中的数量，比最大数量要小的时候 开始创建
          if( that.arr.length < that.maxlength){
            var d = document.createElement("div");
            // 内容和 颜色是随机的 颜色和文字库里面的
            d.innerHTML = that.snowflake[that.random(that.snowflake.length)];
            d.style.color = that.snowflakeColor[that.random(that.snowflakeColor.length)];
            d.style.position = "absolute";
            // 位置是随机的 top(0- -99) left (0 - that.maxWidth*2/3-1)
            d.style.left = that.random(that.maxWidth*2/3) + "px";
            d.style.top = -that.random(100) + "px";
            // 速度
            d.vx = 2+that.random(10);
            d.vy = 3+that.random(10);
            // 数组添加元素, body 添加元素
            document.body.appendChild(d);
            that.arr.push(d)
          }
        },20)
       },
       // 运动
       move : function (){
        var that = this;
        var arr = that.arr;
        setInterval(function (){ 
          // 循环数组中的每一个元素
          for(var i = 0 ; i < arr.length ; i ++ ){
            // 替换位置
            arr[i].style.left = arr[i].offsetLeft + arr[i].vx + "px";
            arr[i].style.top = arr[i].offsetTop + arr[i].vy + 'px';
            // 判断边界 删除元素
            if (arr[i].offsetTop >= that.maxHeight || arr[i].offsetLeft >= that.maxWidth) {
              document.body.removeChild(arr[i]);
              arr.splice(i,1);
            }
          }
        },30)
       }
    }  
    window.onload = function (){
      snowflakes.init(100);
    }  
  </script>
</body>
</html>

效果图