JavaScript Array method filter, map

Array.filter()

The filter() method returns filtered elements in a new array which pass the condition define in callback method

Syntax:

    const newArray = array.filter(function (element, index, array) {

    return condition;

    });

Example: 

   const numbers = [1, 3, 6, 9, 12];

const luckyNumbers = numbers.filter(function(number) {

return number > 7;

});

console.log(luckyNumbers);

// Output: [9, 12]

Array.map()

The map() method creates a new array with the results of calling a function for each element of parent array. This method does not execute for empty element of array.

Syntax:

    const newArray = array.map(function(element, index, arr), thisValue)

Example:        

    // Multiply all the elements of numbers array by 5

const numbers = [1, 2, 3, 4, 5];

const newArray = numbers.map((item) => {

return item * 5;

});

console.log(newArray);

// Output: [5, 10, 15, 20, 25]