I want to join a with b using lodash here is my data
const a =
[ { id: 1, job: 'engineer' }
, { id: 2, job: 'police' }
, { id: 3, job: 'thief' }
]
const b =
[ { name: 'test1', score: 1, aId: [ 1, 2 ] }
, { name: 'test2', score: 3, aId: [ 1, 3 ] }
]
Here is my output that I want
const result =
[ { id: 1, job: 'engineer', score: [ {name: 'test1'}, {name: 'test2'} ] }
, { id: 2, job: 'police', score: [] }
, { id: 3, job: 'thief', score: [ {name: 'test 3'} ] }
]
this is what I try I'm using 2 map data and inside the second map I use include check between 2 arrays..
_.map(a, function(data:any) {
const name = _.map(b, function(dataB:any) {
// in here I check
const isValid = dataB.aId.includes(a.id)
if(isValid){
return {
name = dataB.name
}
}
})
return {
id: data.id
job: data.job
score: name
}
});
this method also work but is their any better method than using 2 map ?
Reduce b to a map of id to array of tests, and then map a, and take the relevant array from the map to create each object:
const a =
[ { id: 1, job: 'engineer' }
, { id: 2, job: 'police' }
, { id: 3, job: 'thief' }
]
const b =
[ { name: 'test1', score: 1, aId: [ 1, 2 ] }
, { name: 'test2', score: 3, aId: [ 1, 3 ] }
]
const bMap = b.reduce((acc, { name, aId }) => {
const nameObject = { name }
aId.forEach(id => {
if(!acc.has(id)) acc.set(id, [])
acc.get(id).push(nameObject)
})
return acc
}, new Map())
const result = a.map(o => ({ ...o, scores: bMap.get(o.id) }))
console.log(result)