es6数组新增2

<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title>数组扩展运算符</title>
	</head>
	<ul id='#oUl'>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
	</ul>
	<body>
		<script type="text/javascript">
			let arr = [1,2,3];
			let arr2 = [...arr];  //...
			console.log(arr);
			console.log(arr2);
			
			
			let strName = 'jiangfei';//类数组：只要具备length就比较靠谱  json在后面必须加入length
			console.log([...strName]);
			console.log([].slice.call(strName));
			console.log(Array.from(strName));
			
			let json = {
				0:"apple",
				1:"banner",
				2:"orange"
			}
			let json2 = {
				0:"apple",
				1:"banner",
				2:"orange",
				length:3
			}
			let json3 = {
				0:"apple",
				1:"banner",
				2:"orange",
				length:2
			}
			console.log(Array.from(json));
			console.log(Array.from(json2));
			console.log(Array.from(json3));
			console.log([].slice.call(json3));
			/*console.log([...json2]);*/
			
			
			/*
			 
			 * arr.keys()每个元素的索引   arr.entriers()所有元素包括索引     ES6数组的特性
			 * */
			
			
			let oUl = document.querySelectorAll('ul li');//伪数组
			let arr3 = [].slice.call(oUl);//将伪数组转换为数组 es5   [].slice.call(伪数组)
			let arr4 = Array.from(oUl);//将伪数组转换为数组 es2015   Array.from(伪数组)把类数组(获取一组元素、arguments...)对象转换为数组  
			let arr5 = [...oUl];//将伪数组转换为数组 es6  [...伪数组]
			console.log(oUl);
			console.log(arr3);
			console.log(arr4);
			console.log(arr5);
					
					
			function show(){
				console.log(arguments);
				console.log(arguments[0]);
				console.log(arguments[1]);
				console.log(arguments[2]);
				let arr6 =[...arguments];
				console.log(arr6);
				console.log(Array.from(arguments));
				console.log([].slice.call(arguments));
				console.log(arguments.length);
			}
			show(1,2,3,4,5)
			
			
			//Array.of()将一组值转成数组 感觉没啥用
			 
			 let strAdd = "'sdgfsagraehdfh','sdgfsagraehdfh'";
			let arr7 = Array.of('aaaa','bbbb','cccc');
			let arr8 = Array.of(strAdd);
			console.log(arr7);
			console.log(arr8);
			
			
			//arr.find(function(val,index,arr){return});查找出第一个符合条件的数组成员，如果没有找到，返回undefined;
			
			let arr9 = [23,12,101,199];
			
			let res = arr9.find((val,index,arr9)=>{
				return val>100;
			});
			console.log(res);
			
			let arrVal = arr9.find(function(val,index,arr9){
				return val>100;
			})
			console.log(arrVal);
		
		//arr9.findIndex((val,index,arr9)=>{return val>100;})  查找出第一个符合条件的数组成员，并返回他的位置，如果没有找到，返回undefined;
		let arrIndex = arr9.findIndex((val,index,arr9)=>{
			return val>100;
		})
		console.log(arrIndex);
		
		//arr.fill(填充的东西,开始位置,结束位置) 包括起始位置，不包括结束位置
		
		let arr10 =new Array(10);
		
		
		arr10.fill('默认值',2,5);
		console.log(arr10)
		
		//arr.includes()判断数组中是否存在指定的元素 返回值为ture/false
		console.log(arr.includes(1));
		
		
		
		</script>
	</body>
</html>
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