基于多个条件的 Javascript 数组排序（一次迭代）

Question

我有一系列汽车：

enum Condition {
  New = 1,
  Used = 2
}

type Car = {
  make: string;
  model: string;
  age: number;
  condition: Condition;
};

const cars: Car[] = [
  {id: "1", make: "BMW", model: "E3", age: 12, condition: Condition.Used},
  {id: "2", make: "Audi", model: "A8", age: 4, condition: Condition.Used},
  {id: "3", make: "Mercedes", model: "SLK", age: 0, condition: Condition.New},
  {id: "4", make: "Ford", model: "CMAX", age: 3, condition: Condition.Used},
  {id: "5", make: "Ford", model: "BMAX", age: 0, condition: Condition.New},
  {id: "6", make: "Porsche", model: "Panamera", age: 0, condition: Condition.New},
]

我有一个搜索查询：

const searchQuery: Car = {
  make: "Ford",
  model: "Panamera",
  age: 4,
  condition: Condition.New
}

我想要一个基于这些规则的排序数组：

• 与品牌（“福特”）完全匹配的商品排在第一位
• 与模型完全匹配的其余部分（“Panamera”）排在第二位
• 其余符合年龄=4的条件
• 其余的都是新的，
• 最后是任何未通过任何测试的项目

首先我做的是过滤与品牌匹配的数组，然后是模型，然后是年龄，等等...... 然后将生成的数组合并到最终数组（也过滤掉通过多个条件的重复项），但这需要迭代cars 的次数与我拥有的条件数量一样多。 所以我想知道是否有更好的方法可以一次性完成？也许以某种方式使用.sort？

Answer 1

您可以创建一个映射函数来确定您的优先级，然后减去排序中的标准化值。

const Condition = { New: 1, Used: 2 };

const cars = [
  {id: "1", make: "BMW", model: "E3", age: 12, condition: Condition.Used},
  {id: "2", make: "Audi", model: "A8", age: 4, condition: Condition.Used},
  {id: "3", make: "Mercedes", model: "SLK", age: 0, condition: Condition.New},
  {id: "4", make: "Ford", model: "CMAX", age: 3, condition: Condition.Used},
  {id: "5", make: "Ford", model: "BMAX", age: 0, condition: Condition.New},
  {id: "6", make: "Porsche", model: "Panamera", age: 0, condition: Condition.New},
];

const searchQuery = {
  make: "Ford",
  model: "Panamera",
  age: 4,
  condition: Condition.New
};

const prioritize = (car, query) => {
  if (car.make === query.make) return 4;
  if (car.model === query.model) return 3;
  if (car.age === query.age) return 2;
  if (car.condition === query.condition) return 1;
  
  return 0;
};

const sorted = cars.sort((a, b) => {
  const prioA = prioritize(a, searchQuery);
  const prioB = prioritize(b, searchQuery);

  return prioB - prioA;
});

console.log(JSON.stringify(sorted, null, 2));

如果您希望排序适用于多个条件，例如首先制作和模型，您可以添加一个简单的递归检查并增加优先级：

const prioritize = (car, query) => {
  const { make, model, age, condition } = query;

  if (car.make === make) return 4 + prioritize(car, { model, age, condition });
  if (car.model === model) return 3 + prioritize(car, { age, condition });
  if (car.age === age) return 2 + prioritize(car, { condition });
  if (car.condition === condition) return 1;

  return 0;
};

在这里，您只需检查下一行的其他查询选项。

Answer 2

我建议使用不同的方法，先检查想要的第一个排序条件，然后再检查较低的条件。

这种方法首先使用新条件对 ford 进行排序，而不是仅先进行 ford。

const
    Condition = { New: 1, Used: 2 },
    cars = [{ id: "1", make: "BMW", model: "E3", age: 12, condition: Condition.Used }, { id: "2", make: "Audi", model: "A8", age: 4, condition: Condition.Used }, { id: "3", make: "Mercedes", model: "SLK", age: 0, condition: Condition.New }, { id: "4", make: "Ford", model: "CMAX", age: 3, condition: Condition.Used }, { id: "5", make: "Ford", model: "BMAX", age: 0, condition: Condition.New }, { id: "6", make: "Porsche", model: "Panamera", age: 0, condition: Condition.New }],
    searchQuery = { make: "Ford", model: "Panamera", age: 4, condition: Condition.New };

cars.sort((a, b) => 
    (b.make === searchQuery.make) - (a.make === searchQuery.make) ||
    (b.model === searchQuery.model) - (a.model === searchQuery.model) ||
    (b.age === searchQuery.age) - (a.age === searchQuery.age) ||
    (b.condition === searchQuery.condition) - (a.condition === searchQuery.condition)
);

console.log(cars); // 5 4 6 2 3 1 instead of 4 5 6 1 2 3

.as-console-wrapper { max-height: 100% !important; top: 0; }

Answer 3

可以认为是优先排序。给出不同的优先级（分）并计算总分。

JS 版本

var Condition;
(function (Condition) {
  Condition[(Condition["New"] = 1)] = "New";
  Condition[(Condition["Used"] = 2)] = "Used";
})(Condition || (Condition = {}));

const priority = {
  make: 5,
  model: 4,
  age: 3,
  condition: 2,
};
const calculatePoint = (obj, params) =>
  Object.entries(obj).reduce((p, [key, value]) => {
    if (value === params[key]) p += priority[key];
    return p;
  }, 0);
const sortData = (data, params) =>
  data.sort((x, y) => calculatePoint(y, params) - calculatePoint(x, params));

const cars = [{"id":"1","make":"BMW","model":"E3","age":12,"condition":2},{"id":"2","make":"Audi","model":"A8","age":4,"condition":2},{"id":"3","make":"Mercedes","model":"SLK","age":0,"condition":1},{"id":"4","make":"Ford","model":"CMAX","age":3,"condition":2},{"id":"5","make":"Ford","model":"BMAX","age":0,"condition":1},{"id":"6","make":"Porsche","model":"Panamera","age":0,"condition":1}]
const searchQuery = {
  make: "Ford",
  model: "Panamera",
  age: 4,
  condition: Condition.New,
};
console.log(sortData(cars, searchQuery));

TS 版本

enum Condition {
  New = 1,
  Used = 2,
}

type Car = {
  id?: string;
  make: string;
  model: string;
  age: number;
  condition: Condition;
};

const cars: Car[] = [{"id":"1","make":"BMW","model":"E3","age":12,"condition":2},{"id":"2","make":"Audi","model":"A8","age":4,"condition":2},{"id":"3","make":"Mercedes","model":"SLK","age":0,"condition":1},{"id":"4","make":"Ford","model":"CMAX","age":3,"condition":2},{"id":"5","make":"Ford","model":"BMAX","age":0,"condition":1},{"id":"6","make":"Porsche","model":"Panamera","age":0,"condition":1}]
;
const searchQuery: Car = {
  make: "Ford",
  model: "Panamera",
  age: 4,
  condition: Condition.New,
};

const priority = {
  make: 5,
  model: 4,
  age: 3,
  condition: 2,
};
const calculatePoint = (obj: Car, params: Car) =>
  Object.entries(obj).reduce((p: number, [key, value]) => {
    if (value === params[key]) p += priority[key];
    return p;
  }, 0);
const sortData = (data: Car[], params: Car) =>
  data.sort(
    (x: Car, y: Car) => calculatePoint(y, params) - calculatePoint(x, params)
  );
console.log(sortData(cars, searchQuery));