javascript数据转换

Question

把arr的数组和oldArr数组匹配，并把相同的替换，并且升序，形成newArr那样子
let arr=[
{type: 4, name: '苹果', order: 4},
{type: 3, name: '香蕉', order: 1},
]
let oldArr=[
{type: 4, name: '苹果', order: 1},
{type: 2, name: '橘子', order: 2},
{type: 1, name: '木瓜', order: 3},
{type: 3, name: '香蕉', order: 4},
]
let newArr=[
{type: 3, name: '香蕉', order: 1},
{type: 2, name: '橘子', order: 2},
{type: 1, name: '木瓜', order: 3},
{type: 4, name: 苹果'', order: 4},
]

Answer 1

示例代码如下

    let arr = [
        { type: 4, name: '苹果', order: 4 },
        { type: 3, name: '香蕉', order: 1 },
    ]
    let oldArr = [
        { type: 4, name: '苹果', order: 1 },
        { type: 2, name: '橘子', order: 2 },
        { type: 1, name: '木瓜', order: 3 },
        { type: 3, name: '香蕉', order: 4 },
    ]
    for (let item of arr) {
        var olditem = oldArr.find(i => i.name == item.name);//从oldArr中找到和arr当前遍历项name一样的项目
        if (olditem) olditem.order = item.order;//存在项目替换order的值
    }
    oldArr.sort((a, b) => { return a.order - b.order });
    console.log(JSON.stringify(oldArr,null,2))

整个项目替换用下面的，效果一样

    let arr = [
        { type: 4, name: '苹果', order: 4 },
        { type: 3, name: '香蕉', order: 1 },
    ]
    let oldArr = [
        { type: 4, name: '苹果', order: 1 },
        { type: 2, name: '橘子', order: 2 },
        { type: 1, name: '木瓜', order: 3 },
        { type: 3, name: '香蕉', order: 4 },
    ]
    for (let item of arr) {
        var index = oldArr.findIndex(i => i.name == item.name);//从oldArr中找到和arr当前遍历项name一样的项目下标
        if (index != -1) oldArr[index] = item;//找到个替换
    }
    oldArr.sort((a, b) => { return a.order - b.order });
    console.log(JSON.stringify(oldArr,null,2))