有人知道一种方法(lodash如果可能的话)通过对象键分组对象数组,然后根据分组创建一个新的对象数组吗?例如,我有一个汽车对象数组:
const cars = [
{
'make': 'audi',
'model': 'r8',
'year': '2012'
}, {
'make': 'audi',
'model': 'rs5',
'year': '2013'
}, {
'make': 'ford',
'model': 'mustang',
'year': '2012'
}, {
'make': 'ford',
'model': 'fusion',
'year': '2015'
}, {
'make': 'kia',
'model': 'optima',
'year': '2012'
},
];
我想创建一个新的汽车对象数组,由make分组:
const cars = {
'audi': [
{
'model': 'r8',
'year': '2012'
}, {
'model': 'rs5',
'year': '2013'
},
],
'ford': [
{
'model': 'mustang',
'year': '2012'
}, {
'model': 'fusion',
'year': '2015'
}
],
'kia': [
{
'model': 'optima',
'year': '2012'
}
]
}
只需简单的forEach循环就可以在这里工作,不需要任何库
var cars = [
{
'make': 'audi',
'model': 'r8',
'year': '2012'
}, {
'make': 'audi',
'model': 'rs5',
'year': '2013'
}, {
'make': 'ford',
'model': 'mustang',
'year': '2012'
}, {
'make': 'ford',
'model': 'fusion',
'year': '2015'
}, {
'make': 'kia',
'model': 'optima',
'year': '2012'
},
];
let ObjMap ={};
cars.forEach(element => {
var makeKey = element.make;
if(!ObjMap[makeKey]) {
ObjMap[makeKey] = [];
}
ObjMap[makeKey].push({
model: element.model,
year: element.year
});
});
console.log(ObjMap);
letfinaldata=[]
let data =[{id:1,name:"meet"},{id:2,name:"raj"},{id:1,name:"hari"},{id:3,name:"hari"},{id:2,name:"ram"}]
data = data.map((item)=>
{
return {...item,
name: [item.name]
}
}) // Converting the name key from string to array
let temp = [];
for(let i =0 ;i<data.length;i++)
{
const index = temp.indexOf(data[i].id) // Checking if the object id is already present
if(index>=0)
{
letfinaldata[index].name = [...letfinaldata[index].name,...data[i].name] // If present then append the name to the name of that object
}
else{
temp.push(data[i].id); // Push the checked object id
letfinaldata.push({...data[i]}) // Push the object
}
}
console.log(letfinaldata)
输出
[ { id: 1, name: [ 'meet', 'hari' ] },
{ id: 2, name: [ 'raj', 'ram' ] },
{ id: 3, name: [ 'hari' ] } ]
const reGroup = (list, key) => {
const newGroup = {};
list.forEach(item => {
const newItem = Object.assign({}, item);
delete newItem[key];
newGroup[item[key]] = newGroup[item[key]] || [];
newGroup[item[key]].push(newItem);
});
return newGroup;
};
const animals = [
{
type: 'dog',
breed: 'puddle'
},
{
type: 'dog',
breed: 'labradoodle'
},
{
type: 'cat',
breed: 'siamese'
},
{
type: 'dog',
breed: 'french bulldog'
},
{
type: 'cat',
breed: 'mud'
}
];
console.log(reGroup(animals, 'type'));
const cars = [
{
'make': 'audi',
'model': 'r8',
'year': '2012'
}, {
'make': 'audi',
'model': 'rs5',
'year': '2013'
}, {
'make': 'ford',
'model': 'mustang',
'year': '2012'
}, {
'make': 'ford',
'model': 'fusion',
'year': '2015'
}, {
'make': 'kia',
'model': 'optima',
'year': '2012'
},
];
console.log(reGroup(cars, 'make'));