1. Array.from(v) : 将伪数组对象或可遍历对象转换为真数组
<body>
<div>div1</div>
<div>div2</div>
<div>div3</div>
<br>
<script>
let divs = document.getElementsByTagName('div');
var arrDiv=''
Array.from(divs).forEach(function (item, index) {
console.log(item, index);
})
</script>
</body>
2. Array.of(v1, v2, v3) : 将一系列值转换成数组
let arr = Array.of(1, 'abc', true);
console.log(arr instanceof Array);//true
3. find(function(value, index, arr){return true}) : 找出第一个满足条件返回true的元素
let arr1 = [1,3,5,2,6,7,3]; let result = arr1.find(function (item, index) { return item >3 }); console.log(result);//5
4 findIndex(function(value, index, arr){return true}) : 找出第一个满足条件返回true的元素下标
let arr1 = [1,3,5,2,6,7,3]; let result1 = arr1.findIndex(function (item, index) { return item >3 }); console.log(result1);//2
5 findIndex(function(value, index, arr){return true}) : 找出第一个满足条件返回true的元素下标
let arr1 = [1,3,5,2,6,7,3]; let result1 = arr1.findIndex(function (item, index) { return item >3 }); console.log(result1);//2