如何在特定对象值为最大值的数组中查找对象

Question

嗨下面是 JSON 对象数组

[
  {
    "BookingId": 366024,
    "BookingDetailId": 340708,
    "JobCode" : 13
  },
  {
    "BookingId": 366023,
    "BookingDetailId": 340707,
    "JobCode" : 12
  },
  {
    "BookingId": 366022,
    "BookingDetailId": 340706,
    "JobCode" : 12
   }
]

我想获取特定的数组对象，其中 BookingId 为 Max，而 JobCode 为 12，例如。在上面的数组中我想要对象{ "BookingId": 366023, "BookingDetailId": 340707, "JobCode" : 12 } BookingId为max，JobCode为12.

如何在 angular 6

尝试过代码

var a = this.GridSource.find(x => x.JobCode == 12 && 
x.BookingId == Math.max.apply(Math, this.GridSource.map
(function(o) { return o.BookingId; })));

Answer 1

您可以为此使用reduce。我在下面做了一个例子，希望这会有所帮助。如果没有满足条件的项目，则 reduce 的结果将是 null

此外，不要忘记类型:)

interface GridItem {
  BookingId: number;
  BookingDetailId: number;
  JobCode: number;
}

const GridSource: GridItem[] = [
  {
    BookingId: 366024,
    BookingDetailId: 340708,
    JobCode: 13
  },
  {
    BookingId: 366023,
    BookingDetailId: 340707,
    JobCode: 12
  },
  {
    BookingId: 366022,
    BookingDetailId: 340706,
    JobCode: 12
  }
];

const foundGridItem: GridItem = GridSource.reduce(
  (result: GridItem, value: GridItem) =>
    value.JobCode === 12 &&
    (result === null || value.BookingId > result.BookingId)
      ? value
      : result,
  null
);

Answer 2

你可以利用reduce找到最大元素，然后在find中使用它。

var max = array.reduce(function(prev, curr) {
    return prev['BookingId'] > curr['BookingId'] ? prev : curr;
});

var elem = array.find(x => x['JobCode'] == 12 && x['BookingId'] == max['BookingId']);

如何在特定对象值为最大值的数组中查找对象

How to find the object in an array where particular object value is max

json

angular

angular5

angular6