js数组的几种遍历

ES5

普通遍历

	const arr=['han','zhao','chen','li','zhang','xi']
	for(let i=0;i<arr.length;i++){
		console.log(arr[i])
	}

for in遍历

迭代出来的是下标

	const arr=['han','zhao','chen','li','zhang','xi']
	for(let index in arr){
		console.log(arr[index])
	}

for of遍历

不能遍历普通对象

迭代出来的是值

	const arr=['han','zhao','chen','li','zhang','xi']
	for(let value of arr){
		console.log(value)
	}

ES6

箭头函数

	const arr=['han','zhao','chen','li','zhang','xi']
	arr.forEach(function(value,index)=>{
		console.log(index+'  '+value)
	})

	//简易写法(两个参数)
	arr.forEach((value,index)=>{
		console.log(index+'  '+value)
	})

	//简易写法(一个参数)
	arr.forEach((value)=>{
		console.log(value)
	})