js数组分割方法，自定义分割长度

函数：

    function splitArray(arr,size) {
      let result = [];
      while (arr.length > 0) {
        let currentChunk = arr.splice(0, size);
        result.push(currentChunk);
      }

      return result;
    }

注意：重点是要理解数组的splice方法会改变原数组

算法思路：当原数组长度大于0时，原数组不断切割长度size，知道原数组长度小于等于0

事例：

    <script>
    let arr=[1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61]
    console.log(splitArray(arr,30));
    function splitArray(arr,size) {
      let result = [];
      while (arr.length > 0) {
        let currentChunk = arr.splice(0, size);
        result.push(currentChunk);
      }

      return result;
    }
    </script>

 输出：