What is Array.prototype.map() in JavaScript?
In JavaScript, the map() method creates a new array from an existing array. It calls a provided callback function on every array element. map() does not mutate the original array.
Parameters
The map() method accepts the following two parameters.
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function: It is a required parameter called on every element of the array. It accepts the following three parameters.-
value: A required parameter. It holds the value of the current element of the array. -
index: This is an optional parameter, as it holds the index of the current element of the array. -
array: This is an optional parameter. It holds the actual array on whichmap()is called.
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this: It is an optional parameter and specifies the value of this pointer while executing the callback function.
Syntax
array.map(function(value, index, array), this);
Return value
The map() method returns a new array populated with the result of the callback function on each element of the existing array.
Code
The following example illustrates the use of map() method.
const array = [4, 5, 7, 15, 1, 2, 6, 8, 1, 10];const newArray = array.map(ele => ele * 3);console.log(newArray);
