es6中一些新增的js方法（常用的函数汇总）

最新推荐文章于 2024-10-08 12:51:09 发布

前端小问题

最新推荐文章于 2024-10-08 12:51:09 发布

阅读量399

点赞数 1

分类专栏： es6 文章标签： js javascript

本文链接：https://blog.youkuaiyun.com/weixin_43989837/article/details/114738641

版权

es6 专栏收录该内容

7 篇文章

订阅专栏

<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
	</head>
	<body>
		<img src="img/video_image02.png" >
	</body>
	<script type="text/javascript">
		
		(function setFun (){
			const arr =[1,1,"1","1",2,2];
			console.log(new Set(arr)); // 返回值为一个对象：  {1, "1", 2}
		});
		
		(function formFun(){
			const arr =[1,1,"1","1",2,2];
			console.log(Array.from(new Set(arr))); // 返回值为一个数组：  [1, "1", 2]
			// arr = Array.from(new Set(arr))
			// console.log(arr)
		})()
		
		
		function sortFun(){
			var arr = ['100', '10', '1000'];
			console.log(arr.sort()); //不穿参数时，默认的是升序排列  ['10','100','1000']
			
			console.log(arr.sort(function(a,b){
				return a - b;
			})); //第一个值大于第二个是升序 ['10','100','1000']
			
			console.log(arr.sort(function(a,b){
				return b - a;
			})); //第二个值大于第一个是升序 ['1000','100','10']
			
		}
		sortFun();
		
		function splicefun(){
			var arr = ['100', '10', '1000'];
				arr1 = arr.splice(1,1,"30");
			console.log(arr1); // ['10']
			console.log(arr);	//  ['100', '30', '1000']
		};
		function splicefun(){
			// 数组的遍历
			var a = [5,6,7,8];
			console.log(a.splice(1,0,9)); //[]
			console.log(a);  // [5, 9, 6, 7, 8]
			var b = [5,6,7,8];
			console.log(b.splice(1,2,3));  //[6, 7]
			console.log(b); //[5, 3, 8]
		}
		splicefun();
		
		// 数组的检测
		const array = [1,1,2,3];
		console.log(array instanceof Array);//true
		console.log(array.constructor === Array); //true
		console.log(typeof(array)); //object
		console.log(Array.isArray(array)) // true
		// const array = new Array();
		
		// array.constructor === Array; // true
		
		
		// const array = new Array();
		
		Array.isArray(array); //true
		
		// let time = DateTime.local()
		//         .setZone('America/New_York')
		//         .toFormat('yyyy-MM-dd HH:mm:ss');
		// console.log(time);
		
		function sort(arr) {
		 if (arr.length===1) return arr
		
		 //分成两部分
		 let mid=Math.floor(arr.length/2)
		 let [part1,part2]=[sort(arr.slice(0,mid)),sort(arr.slice(mid))]
		
		 //对比+合并
		 let result=[]
		 while (part1.length>0&&part2.length>0)
		  result.push((part1[0]<part2[0]?part1:part2).shift())
		 return [...result,...part1,...part2]
		}
		var need =[10,15,30,16,18,3,50,100,2];
		console.log(sort(need));
		// var  part1 = [1,3,5];
		// var  part2 = [2,8,7];
		// console.log(part1[0]<part2[0]?part1:part2);
		// console.log((part1[0]<part2[0]?part1:part2).shift());
		// console.log(part1)
		// console.log(part2)
	</script>
</html>