Question

我在这样的快速后端中得到了一个JSON对象数组，每个对象都包含一个数组，其键名为projectTags：

[ { projectTags: [ 'rer' ] },
  { projectTags: [ 'a10' ] },
  { projectTags: [ 'a10', 'c12', 'e14' ] },
  { projectTags: [ 'a10', 'e14', 'b11', 'c12', 'd13' ] } ]

我想将这些数组合并在一起，结果也将没有相同的标签。因此理想情况下，它看起来应该像这样：

[ { projectTags: [ 'rer', 'a10', 'c12', 'e14', 'b11', 'd13' ] },]

那我该怎么做呢？

Answer 1

使用concat可以创建一个数组，使用Set可以获取唯一值：

const data = [ { projectTags: [ 'rer' ] },{ projectTags: [ 'a10' ] }, { projectTags: [ 'a10', 'c12', 'e14' ] }, { projectTags: [ 'a10', 'e14', 'b11', 'c12', 'd13' ] } ];
  
const result = [{ projectTags: [...new Set([].concat(...data.map(o => o.projectTags)))]}];
  
console.log(result);

Answer 2

您可以将地图OnPropertyChanged() {归入一个尚未添加的元素reduce。

concat

Answer 3

您可以使用Set并添加所有标签。

var data = [{ projectTags: ['rer'] }, { projectTags: ['a10'] }, { projectTags: ['a10', 'c12', 'e14'] }, { projectTags: ['a10', 'e14', 'b11', 'c12', 'd13'] }],
    result = [{ projectTags: Array.from(
        data.reduce(
            (s, { projectTags }) => (
                projectTags.forEach(Set.prototype.add, s),
                s
            ),
            new Set
       )
    ) }];
    
console.log(result)  ;

Answer 4

如果您不需要重复：

var arr = [ { projectTags: ['rer'] },
            { projectTags: ['a10'] },
            { projectTags: ['a10', 'c12', 'e14'] },
            { projectTags: ['a10', 'e14', 'b11', 'c12', 'd13'] }];

var arr2 = [];

arr.forEach(function (e) { 
    var i = e.projectTags;
    for (var x = 0; x < i.length; x++) { 
        if (arr2.indexOf(i[x]) == -1) arr2.push(i[x]);
    } 
});

console.log(arr2);

Answer 5

这是我用JavaScript编写的代码。希望对您有帮助。

//问题中提供的数据列表。

 var dataList = [ 
                { projectTags: [ 'rer' ] },
                { projectTags: [ 'a10' ] },
                { projectTags: [ 'a10', 'c12', 'e14' ] },
                { projectTags: [ 'a10', 'e14', 'b11', 'c12', 'd13' ] } 
            ];

//Final Result
            var dataListAfterMerge = [];
//the list of unique items to be added.
            var items = [];
//to verify if the item is already present in the new list (i.e. items).
            var isAdded = false;

//Call this function on button click or any place you needed.
            merge = function() {
                for (var data of dataList){
                    for(var item of data.projectTags) {
                        for(var newItem of items) {
                            if(item == newItem) {
                                isAdded = true;
                                break;
                            }
                        }

                        if(!isAdded) {
                            items.push(item);
                        }

                        isAdded = false;
                    }
                }
                dataListAfterMerge.push({projectTags: items});

                console.log(dataListAfterMerge);
            }

Answer 6

您可以使用reduce创建一个将所有元素放在一起的数组，然后使用Set删除所有重复项：

const arr = [ { projectTags: ['rer'] },
            { projectTags: ['a10'] },
            { projectTags: ['a10', 'c12', 'e14'] },
            { projectTags: ['a10', 'e14', 'b11', 'c12', 'd13'] }];

const withoutDuplicates = [... new Set(arr.reduce((newArray, element) => {
    newArray.push(...element.projectTags);
    return newArray;
}, []))];

如何在JSON对象数组中合并数组？

6 个答案: