JavaScript Array’s map () Method
The JavaScript Array’s map () method is a high-order array function in JavaScript that allows you to transform each element of an array according to a given mapping function.
JavaScript map() method iterates through the elements of the array, applies the provided function to each element, and creates a new array with the results of these function calls. The original array remains unchanged.
Basic syntax for map() method :
const newArray = originalArray.map(function(currentValue, index, array) {
// return transformed value based on currentValue
});
- currentValue: The current element being processed in the array.
- index: The index of the current element.
- array: The array being iterated.
For example, suppose you have the following array element:
let arr = [3, 4, 5, 6];
Now imagine you are required to multiply each of the array’s elements by 3. You might consider using a for loop as follows:
let arr = [3, 4, 5, 6];
for (let i = 0; i < arr.length; i++){
arr[i] = arr[i] * 3;
}
console.log(arr); // [9, 12, 15, 18]
Iterate over an array using for loop
But you can actually use the Array map() method to achieve the same result. Here’s an example:
let arr = [3, 4, 5, 6];
let modifiedArr = arr.map(function(element){
return element *3;
});
console.log(modifiedArr); // [9, 12, 15, 18]
Iterate over an array using map() method
