拆分數組 形成二維數組

拆分數組 

let setChunk = function (Arr, num){
    class Chunk {
        constructor (list, num) {
            this.list = list || []
            this.num = num || 2
            this.end = []
        }
        add (val) {
            this.end.push(val)
        }
        run () {
            while (this.list.length) {
                if (this.list.length >= this.num) {
                    this.add(this.list.splice(0, this.num))
                } else {
                    this.add(this.list)
                    this.list = []
                }
            }
            return this.end
        }
    }
    Arr = JSON.stringify(Arr)
    Arr = JSON.parse(Arr)
    let p1 = new Chunk(Arr, num)
    return p1.run()
}
let list = ['a', 'b', 'c', 'd', 'e']
// 不修改原數組 返回新數組
console.log(setChunk(list, 3))
console.log(setChunk(list, 2))

結果