reduce过滤数组

原始数据

const data = [{
        id: 1,
        spec: '规格1',
        rules: [{
                rank: 10,
                breaks: 100
            },
            {
                rank: 50,
                breaks: 10
            },
            {
                rank: 100,
                breaks: 5
            }
        ]
    },
    {
        id: 2,
        spec: '规格2',
        rules: [{
                rank: 10,
                breaks: 200
            },
            {
                rank: 50,
                breaks: 20
            },
            {
                rank: 100,
                breaks: 25
            }
        ]
    }
];

使用 forEach 遍历

function skuFormat(data) {
    let RankList = [];
    data.forEach(item => {
        item.rules.forEach(ite => {
            if (RankList.indexOf(ite.rank) === -1) RankList.push(ite.rank);
        })
    })
    let newData = [];
    RankList.forEach(item => {
        newData.push({
            rank: item,
            skus:[]
        })
    })
    newData.forEach(item=>{
        data.forEach(ite=>{
            let Remark={
                id:ite.id,
                spec:ite.spec,
                breaks:0
            }
            try {
                ite.rules.forEach(it=>{
                if(item.rank===it.rank){
                    Remark.breaks=it.breaks;
                    item.skus.push(Remark);
                    throw(new Error('find item'));
                }
            })
            } catch (error) {
            }
        })
    })
    return newData;
}
let newData= skuFormat(data);
console.log(newData)

使用 reduce 处理

let newData=data.reduce((pre, cur) => {
    console.log(cur,pre)
    const list = cur.rules.map(item => ({
        rank: item.rank,
        skus: [{
            id: cur.id,
            spec: cur.spec,
            breaks: item.breaks
        }]
    }))
    if (!pre.length) {
        return list;
    }
    return pre.map((item, key) => {
        return {
            ...item,
            skus: [...item.skus, ...list[key].skus]
        }
    })
}, []);
console.log(newData)

 

来源：https://www.cnblogs.com/gitByLegend/p/11739044.html