JavaScript:删除共享相同属性值的对象的重复项

Question

我有一个对象数组，我想根据特定的key:value 对来 trim 它们。我想创建一个数组，其中每个特定 key:value 对仅包含一个对象。将重复项中的哪个对象复制到新数组并不一定重要。

例如，我想根据 arrayWithDuplicates 的 price 属性进行 trim ，创建一个仅包含每个值之一的新数组:

var arrayWithDuplicates = [
  {"color":"red", 
    "size": "small",
    "custom": {
      "inStock": true,
      "price": 10
    }
  },
  {"color":"green", 
    "size": "small",
    "custom": {
      "inStock": true,
      "price": 30
    }
  },
  {"color":"blue", 
    "size": "medium",
    "custom": {
      "inStock": true,
      "price": 30
    }
  },
  {"color":"red", 
    "size": "large",
    "custom": {
      "inStock": true,
      "price": 20
    }
  }
];

会变成:

var trimmedArray = [
  {"color":"red", 
    "size": "small",
    "custom": {
      "inStock": true,
      "price": 10
    }
  },
  {"color":"green", 
    "size": "small",
    "custom": {
      "inStock": true,
      "price": 30
    }
  },
  {"color":"red", 
    "size": "large",
    "custom": {
      "inStock": true,
      "price": 20
    }
  }
];

是否有 JavaScript 或 Angular 函数可以循环执行此操作？

EDIT: The property to filter on is nested within another property.

Answer 1

此函数通过返回一个新值来从数组中删除重复值。

function removeDuplicatesBy(keyFn, array) {
    var mySet = new Set();
    return array.filter(function(x) {
        var key = keyFn(x), isNew = !mySet.has(key);
        if (isNew) mySet.add(key);
        return isNew;
    });
}

var values = [{color: "red"}, {color: "blue"}, {color: "red", number: 2}];
var withoutDuplicates = removeDuplicatesBy(x => x.color, values);
console.log(withoutDuplicates); // [{"color": "red"}, {"color": "blue"}]

所以你可以像这样使用它

var arr = removeDuplicatesBy(x => x.custom.price, yourArrayWithDuplicates);