How would I go about filtering an array based on specific properties within it?
For example, if I only wanted the objects with the season property in them.
[
{
population: 121321313,
location: 'American city in the East',
},
{
season: 'winter',
population: 54646546,
location: 'Canadian city in the East',
},
{
population: 6546467,
location: 'American city in the West',
},
{
season: 'fall',
population: 145313,
location: 'American city in the South',
},
{
population: 12673,
location: 'Canadian city2 in the East',
},
{
population: 141313,
location: 'Canadian city in the South',
},
{
season: 'fall',
population: 1264473,
location: 'Canadian city4 in the East',
},
{
population: 12673,
location: 'Canadian city6 in the South',
},
];
You're looking for Object#hasOwnProperty. Specifially, you're looking to filter your array to only the items which have the property season which you can accomplish like this:
const cities = [
{ "population": 121321313, "location": "American city in the East" },
{ "season": "winter", "population": 54646546, "location": "Canadian city in the East" },
{ "population": 6546467,"location": "American city in the West"},
{ "season": "fall", "population": 145313, "location": "American city in the South" },
{ "population": 12673, "location": "Canadian city2 in the East" },
{ "population": 141313, "location": "Canadian city in the South" },
{ "season": "fall", "population": 1264473, "location": "Canadian city4 in the East" },
{ "population": 12673, "location": "Canadian city6 in the South" }
];
const filteredCities = cities.filter(x => x.hasOwnProperty("season"));
console.dir(filteredCities);You could also use the more modern Reflect.has. See Javascript object.hasOwnProperty() vs Reflect.has() or How do I check if an object has a specific property in JavaScript? for more information.
const cities = [
{ "population": 121321313, "location": "American city in the East" },
{ "season": "winter", "population": 54646546, "location": "Canadian city in the East" },
{ "population": 6546467,"location": "American city in the West"},
{ "season": "fall", "population": 145313, "location": "American city in the South" },
{ "population": 12673, "location": "Canadian city2 in the East" },
{ "population": 141313, "location": "Canadian city in the South" },
{ "season": "fall", "population": 1264473, "location": "Canadian city4 in the East" },
{ "population": 12673, "location": "Canadian city6 in the South" }
];
const filteredCities = cities.filter(x => Reflect.has(x, "season"));
console.dir(filteredCities);you can use statement - for..of, for iterate objects then find your items and push to the new array
const list = [
{
"population": 121321313,
"location": "American city in the East"
},
{
"season": "winter",
"population": 54646546,
"location": "Canadian city in the East"
},
{
"population": 6546467,
"location": "American city in the West"
},
{
"season": "fall",
"population": 145313,
"location": "American city in the South"
},
{
"population": 12673,
"location": "Canadian city2 in the East"
},
{
"population": 141313,
"location": "Canadian city in the South"
},
{
"season": "fall",
"population": 1264473,
"location": "Canadian city4 in the East"
},
{
"population": 12673,
"location": "Canadian city6 in the South"
}
];
let Newarr = [];
for (const item of list) {
if(Object.hasOwn(item, "season")) {
Newarr.push(item);
}
}
console.log(Newarr);