js对象数组按照一定规律重新组合

 将js对象数组按照相同属性重新组合成一个新的对象数组

查询出来的数据是这样的： 

 

目前的数据是这样的，每个品牌都有对应7个月份的折扣数据，但是我想获得的数据效果是这样的 ：

目前想了好久，唯一想到的方法就是将查出来的数据，重新组合成一个包含各品牌及其每个月折扣的对象数组

var brandDiscountArr = [] // 重新组合的品牌数据数组
var discountObj = {} //各品牌每月销量对象
var brandNameSet = new Set(); // 所有品牌
this.brandDiscountList.forEach(x => brandNameSet.add(x.brandName)); // 利用set去重获取数组中的所有品牌名称
for (let s of brandNameSet.keys()) { // 先遍历每个品牌
    discountObj = {}
    this.brandDiscountList.forEach(item => { // 在遍历所有数据，按照品牌名称组建数组
        if(item.brandName === s){
            discountObj.brandName = item.brandName
            if(item.month === '1月'){
                discountObj.Jan = item.discountRate
            }
            if(item.month === '2月'){
                discountObj.Feb = item.discountRate
            }
            if(item.month === '3月'){
                discountObj.Mar = item.discountRate
            }
            if(item.month === '4月'){
                discountObj.Apr = item.discountRate
            }
            if(item.month === '5月'){
                discountObj.May = item.discountRate
            }
            if(item.month === '6月'){
                discountObj.Jun = item.discountRate
            }
            if(item.month === '7月'){
                discountObj.Jul = item.discountRate
            }
        }
    })
    brandDiscountArr.push(discountObj)
}
    this.brandDiscountArr = brandDiscountArr

 

 最终得到的数组效果如下

 

js对象数组根据某个共同字段重新分组

希望的是将下面的对象数组：

[
    {"id":"1001","name":"值1","value":"111"},
    {"id":"1001","name":"值1","value":"11111"},
    {"id":"1002","name":"值2","value":"25462"},
    {"id":"1002","name":"值2","value":"23131"},
    {"id":"1002","name":"值2","value":"2315432"},
    {"id":"1003","name":"值3","value":"333333"}
]

 

根据相同name字段分组，转换成下面这种形式：

[
    {
        "id": "1001",
        "name": "值1",
        "data": [
            {"id": "1001", "brandName": "值1", "value": "111"},
            { "id": "1001", "brandName": "值1", "value": "11111"}
        ]
    },
    {
        "id": "1002",
        "name": "值2",
        "data": [
            { "id": "1002",  "brandName": "值2", "value": "25462" },
            { "id": "1002", "brandName": "值2", "value": "23131"},
            {"id": "1002", "brandName": "值2","value": "2315432" }
        ]
    },
    {
        "id": "1003",
        "name": "值3",
        "data": [
            {"id": "1003", "brandName": "值3", "value": "333333" }
        ]
    }
]

 

做法：

var arr = [
    {"id":"1001","brandName":"值1","value":"111"},
    {"id":"1001","brandName":"值1","value":"11111"},
    {"id":"1002","brandName":"值2","value":"25462"},
    {"id":"1002","brandName":"值2","value":"23131"},
    {"id":"1002","brandName":"值2","value":"2315432"},
    {"id":"1003","brandName":"值3","value":"333333"}
]
var map = {}
var dest = []
for(var i = 0; i < this.budgetList.length; i++){
    var ai = this.budgetList[i]
    if(!map[ai.brandName]){
        dest.push({
            id: ai.id,
            brandName: ai.brandName,
            data: [ai]
        });
        map[ai.brandName] = ai
    }else{
        for(var j = 0; j < dest.length; j++){
            var dj = dest[j];
            if(dj.brandName== ai.brandName){
                dj.data.push(ai)
                break
            }
        }
    }
}
console.log(JSON.stringify(dest))

 

js两个数组对象根据属性相同的值合并

const a=[{
    uid: 1,
    name: 'apple'
},{
    uid: 2,
    name: 'banana'
}]

const b=[{
    uid: 1,
    unit: 'pcs'
},{
    uid: 2,
    unit: 'kg'
}]

// 期待的效果

c=[{
    uid: 1,
    name: 'apple',
    unit: 'pcs',
},{
    uid: 2,
    name: 'banana',
    unit: 'kg',
}]

// 实现方法
a.map(el => {
    if(b.find(item => item.uid == el.uid) != null){
        el.unit = b.find(item => item.uid == el.uid).unit
    }
})

console.log(a)