清空数组有几种方法

1. 通过将数据的长度置为0

var arr = [1, 2, 3]
arr.length = 0

2.通过splice方法

var arr = [1, 2, 3]
while(arr.length){
	arr.splice(0, 1)
}

3. 直接将数组置为空数组

var arr = [1, 2, 3]
arr = []