i have array of ages, i want to know in what age range are those ages and how many, and then push into my object.
issue i have is that if there is more then 1 age in the same range it pushes twice, i want to push it once and display length of it, but it returns undefiened
here is my stackblitz
this.ages = [18, 20, 1];
this.ages.forEach((a) => {
//infant
if (a >= 0 && a <= 1) {
this.id = 1;
this.travel.listOfTravellerCountPerAgeRange.push({
travellerAgeRangeId: this.id,
travellerCount: a.length,
});
}
//adult
else if (a >= 12 && a <= 59) {
this.id = 3;
this.travel.listOfTravellerCountPerAgeRange.push({
travellerAgeRangeId: this.id,
travellerCount: a.length,
});
}
});
console.log(this.travel);
output i get from console.log is:
listOfTravellerCountPerAgeRange: [
{travellerAgeRangeId: 3, travellerCount: undefined},
{travellerAgeRangeId: 3, travellerCount: undefined},
{travellerAgeRangeId: 1, travellerCount: undefined} ]
output i wanna get:
listOfTravellerCountPerAgeRange: [
{travellerAgeRangeId: 3, travellerCount: 2},
{travellerAgeRangeId: 1, travellerCount: 1} ]
If you want to count some value from the array items, you should use reduce method:
this.travel = {};
this.ages = [1,1,45];
this.travel.listOfTravellerCountPerAgeRange = this.ages.reduce((acc, a) => {
let id
if (a >= 0 && a <= 1) {
id = 1;
} else if (a >= 12 && a <= 59) {
id = 3;
}
const record = acc.find((entry) => entry.travellerAgeRangeId === id);
if (record) {
record.travellerCount += 1;
} else {
acc.push({travellerAgeRangeId: id, travellerCount: 1});
}
return acc;
}, []);
console.log(this.travel.listOfTravellerCountPerAgeRange);I didn't run that code, but it should work =)