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Javascript Array filter method


The filter() Array function takes an existing array and generates a new array with entries that meet a set of criteria. We will look at how to utilize the JavaScript filter array function in this tutorial.


Syntax


array.filter(function(value, index, arr), thisValue)
ParameterDescription
function()For each array element, a function must be executed.
currentValueThis is the current elements value.
indexThe current elements index number.
arrThis is the current elements array.
thisValueA value that will be used by the function. The default value is undefined.

Lets see an example of a filter where we only display numbers greater than 5 in a given array


let numbers = [10,30,-35,2,4,7];

let array = numbers.filter(function(value) {
    return value > 5; });

console.log(array);
Output

[ 10, 30, 7 ]

Lets see how we can use the filter() method in objects.


let colors_array = [{value: "blue"},
                    {value: "green"},
                    {value:"yellow"}];

let select_color = colors_array.filter(function(color) {
    return color.value !== "green"; });

console.log(select_color);
Output

[ { value: 'blue' }, { value: 'yellow' } ]