现有 10 个数据，每 2 个数据进行储存

var arr = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
var result = []

slice

for (let i = 0; i < arr.length; i += 2) {
  result.push(arr.slice(i, i + 2))
}
console.log(result)

splice

for (let i = 0; i < arr.length; i++) {
  result.push(arr.splice(0, 2))
  if (i > arr.length) {
    result.push(arr)
  }
}
console.log(result)