如何从 Array / Angular 中的元素中获取最小值

Question

我有以下数组

[
 0: {
  nameId: "041c1119"
  lastError: null
  spotId: "15808822"
  workType: "1"
 },
 1: {
  nameId: "041c1130"
  lastError: null
  spotId: "15808821"
  workType: "1"
 },
 2: {
  nameId: "041c11123"
  lastError: null
  spotId: "15808820"
  workType: "1"
 }
]

我试图获得最低的spotId 值，在这种情况下我需要获得15808820。 我将不胜感激任何建议的帮助（使用 lodash 的示例会很棒） 谢谢！

Answer 1

不需要任何像Lodash这样的外部库，你可以用纯JS来实现。

这是使用 ES6 特性和Array.reduce() 方法的一行代码的解决方案。

const data = [{
  nameId: "041c1119",
  lastError: null,
  spotId: "15808822",
  workType: "1"
}, {
  nameId: "041c1130",
  lastError: null,
  spotId: "15808821",
  workType: "1"
}, {
  nameId: "041c11123",
  lastError: null,
  spotId: "15808820",
  workType: "1"
}];


const minSpotId = data.reduce((prev, current) => (prev.spotId < current.spotId) ? prev : current);

console.log(minSpotId);

Answer 2

我建议只遍历数组并与现有的最小值进行比较：

const data = [{
  nameId: "041c1119",
  lastError: null,
  spotId: "15808822",
  workType: "1"
}, {
  nameId: "041c1130",
  lastError: null,
  spotId: "15808821",
  workType: "1"
}, {
  nameId: "041c11123",
  lastError: null,
  spotId: "15808820",
  workType: "1"
}];

let minSpotId;

data.forEach(el => {
  if (minSpotId === undefined || parseInt(el.spotId) < minSpotId) {
    minSpotId = parseInt(el.spotId);
  }
});

console.log(minSpotId);

Answer 3

const data = [{
  nameId: "041c1119",
  lastError: null,
  spotId: "15808822",
  workType: "1"
}, {
  nameId: "041c1130",
  lastError: null,
  spotId: "15808821",
  workType: "1"
}, {
  nameId: "041c11123",
  lastError: null,
  spotId: "15808820",
  workType: "1"
}];

const lowest = Math.min.apply(Math, data.map(function(o) {
  return o.spotId
}));

console.log(lowest);