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@@ -0,0 +1,91 @@
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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>Document</title>
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+</head>
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+<body>
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+ <ul>
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+ <li>1</li>
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+ <li>2</li>
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+ <li>3</li>
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+ </ul>
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+ <script>
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+ var arr = [1,2,3,4]
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+ // for(var i=0;i<arr.length;i++){
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+ // console.log(arr[i])
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+ // }
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+ /* forEach() 方法用于调用数组的每个元素,并将元素传递给回调函数。 */
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+ /* arr.forEach((ele,index)=>{
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+ console.log(ele,index)
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+ }) */
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+ /* filter 过滤 过滤出符合条件的 */
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+ /* var arr2 = arr.filter((ele)=>{
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+ return ele > 2
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+ })
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+ console.log(arr2) */
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+
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+ /* var arr3 = [{
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+ name:'zs',
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+ age:18
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+ },{
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+ name:'lisi',
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+ age:20
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+ },{
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+ name:'ww',
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+ age:30
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+ }]
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+ var arr4 = arr3.filter((ele)=>{
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+ return ele.age > 19
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+ })
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+ console.log(arr4) */
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+
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+ /* map 映射出一个新数组 通过指定函数处理数组中的每个元素 返回处理后的数组 */
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+ /* var arr5 = arr.map((ele)=>{
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+ return ele * 2 + 3
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+ })
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+ console.log(arr5)
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+ console.log(arr) */
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+
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+ /* some 检测数组当中的元素是否有符合指定条件的 */
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+ var age = [3,12,18,20,22]
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+ /* var age1 = age.some((ele)=>{
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+ return ele >= 23
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+ })
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+ console.log(age1) */
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+
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+ /* evey 检测数组当中的所有元素是否都符合指定条件 */
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+ /* var age2 = age.every((ele)=>{
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+ return ele >= 3
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+ })
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+ console.log(age2) */
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+
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+ /* ruduce 将数组内的元素计算为一个值 从左到右 */
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+ var num = [88,44,22,18,33]
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+ /* var nums = num.reduce((total,num)=>{
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+ return total + num
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+ })
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+ console.log(nums) */
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+ /* find 在数组内找到第一个满足条件的元素 */
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+ /* var num1 = num.find((ele)=>{
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+ return ele < 23
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+ })
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+ console.log(num1) */
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+ var aLi = document.getElementsByTagName('li')
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+ console.log(aLi)
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+ /* var a = [...aLi]
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+ console.log(a) */
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+
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+ var a = Array.from(aLi)
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+ console.log(a)
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+
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+ /*
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+ 类数组 转化为数组
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+ 1.扩展运算符
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+ 2.Array.from()
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+ */
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+ </script>
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+</body>
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+</html>
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