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@@ -0,0 +1,93 @@
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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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+ /* arr.forEach() */
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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 */
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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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+
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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当中的每个元素，并返回处理后的数组 */
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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(arr)
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+ console.log(arr5)
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+
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+ /* some 检测元素当中是否符合指定条件的元素 */
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+ var age = [6,10,12,18]
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+ // var ages = age.some((ele)=>{
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+ // return ele>=20
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+ // })
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+ // console.log(ages)
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+
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+ /* every 检测数值元素中每个元素都是否符合指定条件 */
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+ var ages = age.every((ele)=>{
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+ return ele>=6
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+ })
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+ console.log(ages)
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+
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+ /* reduce 计算 将元素从左到右计算为和 */
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+ var num = [33,55,66,99]
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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()返回条件下数组的第一个元素的值 */
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+ var num1 = num.find((ele)=>{
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+ return ele > 54
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+ })
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+ console.log(num1)
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+
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+ var aLi = document.getElementsByTagName('li')
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+ console.log(aLi)
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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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+ // var arrn = [...aLi]
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+ // console.log(arrn)
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+
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+ var arrn = Array.from(aLi)
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+ console.log(arrn)
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+ </script>
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+</body>
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+</html>
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zsydgithub