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@@ -0,0 +1,90 @@
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+var arr = [1,2,3,4];
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+var obj = {
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+ name: 'Lucy',
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+ age: 40,
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+ sex: '女'
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+}
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+// for(let i=0;i<arr.length;i++) {
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+// console.log(arr[i]);
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+// }
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+// 1.forEach
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+arr.forEach((ele,index) => {
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+ console.log(ele,'ele');
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+ console.log(index,'index')
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+})
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+// 2.for in:循环的key值是下标（索引） es5新增的 一般用于遍历对象
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+for(key in arr) {
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+ console.log(key,'key')
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+}
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+for(key in obj) {
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+ console.log(key,'obj');
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+}
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+// 3.for of:循环的key值是value值 常用于遍历数组
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+for(keys of arr) {
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+ console.log(keys,'keys')
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+}
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+// for(keys of obj) {
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+// console.log(keys,'keys1')
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+// }
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+// 4.filter 过滤 过滤出符合条件的
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+let arr2 = arr.filter((ele) => {
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+ return ele >= 2;
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+})
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+console.log(arr2,'arr2');
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+
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+let arr3 =[{
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+ name:'LiLi',
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+ age: 18
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+},{
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+ name:'Lucy',
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+ age:20
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+},{
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+ name:"XMing",
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+ age: 30
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+},{
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+ name:"Hua",
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+ age:26
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+}]
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+
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+let arr4 = arr3.filter((ele) => {
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+ return ele.age > 20;
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+})
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+console.log(arr4,'arr4');
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+
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+// 5.map 映射出一个新数组 通过制定函数处理数组当中的每个元素 并将处理完的元素返回到新数组中
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+let arr5 = arr.map((ele)=> {
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+ return ele*2+3;
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+})
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+console.log(arr5,'arr5');
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+console.log(arr,'arr');
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+
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+// 6.some 若有一个值满足条件 则返回 true ；都不满足 才返回false ; 检测元素中是否有符合条件的元素
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+var newArr = [23,45,67,89];
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+let newArr1 = newArr.some((ele) => {
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+ return ele>80;
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+})
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+console.log(newArr1,'newArr1');
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+
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+// 7.every 条件都满足则为true;有一个不满足 则为false; 检测元素中是否有符合条件的元素
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+let newArr2 = newArr.every((ele) =>{
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+ return ele < 100;
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+})
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+console.log(newArr2,'newArr2');
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+
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+// 8.reduce 将元素从左到右计算总和
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+let newArr3 = newArr.reduce((total,num) => {
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+ return total + num;
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+})
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+console.log(newArr3,'newArr3');
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+
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+// 9.find 找到符合条件的第一个元素并返回
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+let newArr4 = newArr.find((ele) => {
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+ return ele >30;
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+})
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+console.log(newArr4,'newArr4');
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+
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+// 10.类数组转成数组 Array.from()
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+var lis = document.querySelectorAll("ul li");
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+console.log(lis,'lis');
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+console.log([...lis],'1');
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+console.log(Array.from(lis),'2');
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