JS清空数组三种方法(前端面试)
1. splice
var arr = [1,2,3,4]
function emptyArray(arr){
return arr.splice(0,arr.length)
}
emptyArray(arr)
console.log(arr) //[]空数组
2. 赋值
var arr = [1,2,3,4]
arr = []
缺点：仅仅改变指针的指向，如果有多个指针都指向了这个数组，只能修改一个
var a = [1,2,3]
var b = a
a = []
3. length
var a = [1,2,3]
a.length = 0
console.log(arr) //[]空数组
