javascript - js整理数组

Question

现在遇到数组转换的问题，比如:下面arr是一个数组
var arr = ['a','b','ac','c','ab','ar','ah','av','aa'];
现在要把这个数组变成：
arrs = [['a','b'],['ac','c'],['ab','ar'],['ah','av'],['aa']];

把arr变成二维数组，按顺序每2个一起，怎么分呢？

Answer 1

来个lowb版本

var arr = ['a', 'b', 'ac', 'c', 'ab', 'ar', 'ah', 'av', 'aa'];

function run(arr, num) {
  let res = [];
  let len = arr.length;
  for (let i = 0; i < len;) res.push(arr.slice(i, i += num));
  return res;
}

console.log(run(arr, 2));

Answer 2

var arr = ['a','b','ac','c','ab','ar','ah','av','aa'];
var arrs = [];
while(arr.length > 0) {
  arrs.push(arr.splice(0,2))
}

Answer 3

来个lowb版本2.0，不破坏原有数组的情况：

var arr = ['a','b','ac','c','ab','ar','ah','av','aa'];
var arrs = [];
for (var i = 0; i < arr.length; i+=2) {
    arrs.push(arr.slice(i, i + 2))
}
console.log(JSON.stringify(arr), JSON.stringify(arrs));

顺便更好的理解splice和slice的用法区别