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@@ -0,0 +1,42 @@
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+<!DOCTYPE html>
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+<html lang="en">
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+<head>
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+ <meta charset="UTF-8">
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+ <meta http-equiv="X-UA-Compatible" content="IE=edge">
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+ <meta name="viewport" content="width=device-width, initial-scale=1.0">
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+ <title>箭头函数应用场景</title>
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+</head>
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+<body>
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+ <div style="width:200px;height:200px;background:green;" id="box"></div>
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+ <script>
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+ // 点击div 2s后变颜色
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+ let ad = document.getElementById("box");
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+ ad.addEventListener('click',function(){
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+ let that = this
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+ setTimeout(function(){
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+ //this指window
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+ that.style.background = 'pink'
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+ },2000)
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+ //箭头
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+ setTimeout(()=>{
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+ this.style.background = 'pink'
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+ })
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+ })
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+ //从数组中返回偶数元素
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+ const arr = [1,2,4,5,3,344]
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+ const result = arr.filter(function(item){
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+ if(item % 2 === 0){
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+ return true;
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+ }else{
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+ return false;
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+ }
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+ })
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+ //箭头
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+ const result = arr.filter(item=>item%2 === 0)
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+
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+ //箭头函数适合与this无关的回调,定时器,数组的方法回调
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+ //不适合与this有关的回调,不适合事件回调,对象的方法
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+
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+ </script>
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+</body>
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+</html>
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