Code examples for Array .filter() method

array-filter-example1.js

let items = [ 1, 2, 3, 4, 5, 6 ]
let filtered = items.filter(x => x > 3)

console.info('filtered:', filtered) // filtered: [ 4, 5, 6 ]

array-filter-example2.js

let stocks = [
  { symbol: "APL", price: 693 },
  { symbol: "HUBC", price: 103 },
  { symbol: "POL", price: 413 }
]

function stocksOver(stocks, minPrice) {
 return stocks.filter(stock => stock.price >= minPrice)
}

let expensiveStocks = stocksOver(stocks, 150)

console.log(expensiveStocks) // [ { symbol: 'APL', price: 693 }, { symbol: 'POL', price: 413 } ]

array-filter-example3.js

let people = [ 
	{name: 'Aamnah', pets: ['cat', 'dog']}, 
	{name: 'Ali', pets: ['dog']},
	{name: 'Simon', pets: ['horse']},
	{name: 'Ben', pets: []}
]

let filter1 = people.filter(x => x.pets.length) // only get objects where the pets property array has a value
console.info('filter1:', filter1)

let filter2 = people.filter(x => x.pets) // only get objects where the pets property exists
console.info('filter2:', filter2)

let filter3 = people.filter(x => x.pets.indexOf('dog') > -1) // only get objects where the pets property contains a dog
console.info('filter3:', filter3)