JavaScript Array filter() Method


The filter() method creates an array filled with all array elements that pass a test (provided as a function).

The filter() Array method creates a new array with elements that fall under a given criteria from an existing array:

var numbers = [1, 3, 6, 8, 11];

var lucky = numbers.filter(function(number) {
  return number > 7;
});

// [ 8, 11 ]
 

The item argument is a reference to the current element in the array as filter() checks it against the condition. This is useful for accessing properties, in the case of objects.

Syntax

array.filter(function(currentValue, index, arr), thisValue)

Example

<p>Minimum age: <input type="number" id="ageToCheck" value="18"></p>
<button onclick="myFunction()">Try it</button>

<p>All ages above minimum: <span id="demo"></span></p>

<script>
var ages = [32, 33, 12, 40];

function checkAdult(age) {
  return age >= document.getElementById("ageToCheck").value;
}

function myFunction() {
  document.getElementById("demo").innerHTML = ages.filter(checkAdult);
}
</script>

Example -