如何将数组中的指定元素移至末尾且保留其余元素原有顺序

需求说明 #

将随机顺序数组中的指定元素从原位置移除，按固定顺序放到数组末尾，其余非指定元素保留原有相对顺序，同时过滤数组中的空值。

实现思路 #

• 第一步：过滤原数组，仅保留不属于后置指定集合、且非空的元素，天然保留原有相对顺序
• 第二步：将固定顺序的指定后置元素拼接在过滤后的数组末尾

代码实现 #

// 封装处理函数，参数为原数组、固定后置元素集合
function processArray(originArr, lastElementList) {
  // 过滤正常元素：排除后置元素 + 排除空值
  const normalElements = originArr.filter(item => {
    return !lastElementList.includes(item) && item.trim() !== ''
  })
  // 拼接固定顺序的后置元素
  return normalElements.concat(lastElementList)
}

// 测试用例
const input_always_place_at_last = ["me","you"]
const download_array1 = ["me","father","mother","sister","you","brother","grandfather","grandmother"]
const download_array2 = ["brother","grandfather","me","grandmother","father","mother","sister","you"]
const download_array3 = ["you","father","mother","grandmother","sister","me","brother","grandfather",""]

// 调用输出
console.log(processArray(download_array1, input_always_place_at_last))
console.log(processArray(download_array2, input_always_place_at_last))
console.log(processArray(download_array3, input_always_place_at_last))

输出结果 #

和需求预期完全一致：

["father","mother","sister","brother","grandfather","grandmother","me","you"]
["brother","grandfather","grandmother","father","mother","sister","me","you"]
["father","mother","grandmother","sister","brother","grandfather","me","you"]

原有代码错误说明 #

你尝试的download_array1.includes(input_always_place_at_last).push(input_always_place_at_last)存在两个核心问题：

1. Array.includes()方法仅支持传入单个元素判断是否存在，直接传入数组input_always_place_at_last只会判断原数组中是否存在该数组作为子元素，永远返回布尔值false，布尔值不存在push方法，运行会直接抛出类型错误。
2. 逻辑缺失：没有先移除原数组中已存在的me、you元素，直接推送会导致这两个元素在数组中重复出现。

内容的提问来源于stack exchange，提问作者user16731842