除了两个数组之间的一个属性之外的对象的交集

Question

我有两个数组，它们包含相同类型的对象（相同的属性但关联的值不同）。我想比较两个数组并匹配除一个属性外相等的对象。然后我想在第一个数组中找到匹配的对象的索引，以便将这些对象推送到不同的数组中。

我认为所有这些都可以使用 lodash 完成，并且我想避免 for 循环，以使其尽可能高效

请注意，我在一个 js 类中工作

这是我的尝试（不工作）

class MatchPlayers {
    constructor(){
        this.TeamA = [
            {weight:'75',height:'170', foot:'Left', available:true},
            {weight:'88',height:'190', foot:'Right', available:true},
            {weight:'65',height:'163', foot:'Right', available:false},
            {weight:'70',height:'168', foot:'Left', available:true}
        ]

        this.TeamB = [
            {weight:'75',height:'170', foot:'', available:true},
            {weight:'93',height:'201', foot:'', available:true},
            {weight:'65',height:'163', foot:'', available:false}
        ]

        this.MatchedPlayers = []
    }

    PlayersMatch (){
        for(this.i=0;this.i<this.TeamA.length;this.i++){
            if (_.intersection(this.TeamA,{weight:this.TeamB.weight, height:this.TeamB.height, available:this.TeamB.available})){
              this.position = _.findIndex(this.TeamA,{weight:this.TeamB.weight, height:this.TeamB.height, available:this.TeamB.available})
              this.MatchedPlayers.push(this.TeamA[this.position])
            } else {console.log('No matchable players')}
          }
        console.log(this.MatchedPlayers)
    }
}

在这种情况下，我想匹配除“脚”之外具有相同属性的对象，因此预期输出为：

//Expected Output:
this.MatchedPlayers = [
    {weight:'75',height:'170', foot:'Left', available:true}, 
    {weight:'65',height:'163', foot:'Right', available:false}
]

Answer 1

您可以采取一种简化的方法并省略foot 属性，并通过_.isEqual 获取左上方属性的交集。

var a = [{ weight: '75', height: '170', foot: 'Left', available: true }, { weight: '88', height: '190', foot: 'Right', available: true }, { weight: '65', height: '163', foot: 'Right', available: false }, { weight: '70', height: '168', foot: 'Left', available: true }],
    b = [{ weight: '75', height: '170', foot: '', available: true }, { weight: '93', height: '201', foot: '', available: true }, { weight: '65', height: '163', foot: '', available: false }],
    omitFoot = o => _.omit(o, 'foot'),
    intersection = _.intersectionWith(
        _.map(a, omitFoot),
        _.map(b, omitFoot),
        _.isEqual
    );

console.log(intersection);

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<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.15/lodash.min.js"></script>

Answer 2

要创建具有自定义行为的交集，请使用_.intersectionWith()。该方法接受一个在两个对象之间进行比较的谓词。在这种情况下，比较几乎与_.isEqual() 相同，但它应该忽略一个属性。

您可以使用_.isEqualWith() 创建谓词，它接受自定义函数。如果比较键（第三个参数）是foot，它应该返回true（等于，因为我们不在乎），如果不是，它应该返回undefined，以便_.isEqualWith()可以进行标准_.isEqual()比较.

const a = [{ weight: '75', height: '170', foot: 'Left', available: true }, { weight: '88', height: '190', foot: 'Right', available: true }, { weight: '65', height: '163', foot: 'Right', available: false }, { weight: '70', height: '168', foot: 'Left', available: true }];
const b = [{ weight: '75', height: '170', foot: '', available: true }, { weight: '93', height: '201', foot: '', available: true }, { weight: '65', height: '163', foot: '', available: false }];

const result = _.intersectionWith(a, b, 
  _.partialRight(_.isEqualWith,
    (...args) => args[2] === 'foot' ? true : undefined
  )
);

console.log(result);

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<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.15/lodash.min.js"></script>