I have the following array and object I would like to 'match'
const items = [
{ key: 1, name: 'A', owner: 'Alex', },
{ key: 2, name: 'B', owner: 'Barb', },
{ key: 3, name: 'C', owner: 'John', },
{ key: 4, name: 'D', owner: 'Barb', },
{ key: 5, name: 'E', owner: 'Alex', },
];
const owners = {
'Alex': { 1: [], 5: [] },
'John': { 3: [], },
'Barb': { 2: [], 4: [] },
}
I would like to have the following end result:
const ownersWithName = {
'Alex': [{ key: 1, name: 'A', }, { key: 5, name: 'E' }],
'Barb': [{ key: 2, name: 'B', }, { key: 4, name: 'D' }],
'John': [{ key: 3, name: 'C', }, ],
}
So far my solution is this:
function matchOwners (items, owners) {
const ownersWithName = {};
for (const item of items) {
if (owners[item.owner]) {
if (ownersWithName[item.owner]) {
ownersWithName[item.owner] = [ ...ownersWithName[item.owner], item];
} else {
ownersWithName[item.owner] = [item];
}
}
}
return ownersWithName;
}
This solution works, but i feel it's too verbose. i tried to use the spread operator without the if condition, but this needs the array to exist already, otherwise i get the error ownersWithName[item.owner] is not iterable
. Is there a better way to do this?
CodePudding user response:
Something like (completely untested):
ownersWithName = items.reduce((result, item) => {
if (owners[item.owner]) {
if (!(item.owner in result)) {
result[item.owner] = [];
}
result[item.owner].push({key: item.key, name: item.name});
}
return result;
}, {})
CodePudding user response:
You can also simply achieve this by using Array.forEach()
along with the Object.keys()
method.
Live Demo (Descriptive comments has been added in the below code snippet) :
// Input array
const items = [
{ key: 1, name: 'A', owner: 'Alex', },
{ key: 2, name: 'B', owner: 'Barb', },
{ key: 3, name: 'C', owner: 'John', },
{ key: 4, name: 'D', owner: 'Barb', },
{ key: 5, name: 'E', owner: 'Alex', },
];
// Input object which should be used to match.
const owners = {
'Alex': { 1: [], 5: [] },
'John': { 3: [], },
'Barb': { 2: [], 4: [] },
};
// Declare an object which will store the final result.
const resultObj = {};
// Iterating over an items array to manipulate the data and make the final result set.
items.forEach(obj => {
resultObj[obj.owner] = !resultObj[obj.owner] ? [] : resultObj[obj.owner];
Object.keys(owners[obj.owner]).forEach(key => {
if (key == obj.key) {
resultObj[obj.owner].push({
key: obj.key,
name: obj.name
});
}
});
});
// Final output
console.log(resultObj);