Identifies the type of the array elements
Identifies the type of the elements returned by the callback function, defaults to T.
The array or array like object of elements to be searched.
The function that is called for evetn element of theArray.
OptionalthisArg: anyThe value to use as the this when executing the callbackFn.
const numbers = [1, 4, 9];
const roots = arrMap(numbers, (num) => Math.sqrt(num));
// roots is now [1, 2, 3]
// numbers is still [1, 4, 9]
const kvArray = [{ key: 1, value: 10 },
{ key: 2, value: 20 },
{ key: 3, value: 30 }];
const reformattedArray = arrMap(kvArray, ({ key, value}) => ({ [key]: value }));
// reformattedArray is now [{1: 10}, {2: 20}, {3: 30}],
// kvArray is still:
// [{key: 1, value: 10},
// {key: 2, value: 20},
// {key: 3, value: 30}]
// Also supports Array Like objects with same output
const kvArray = {
length: 3,
0: { key: 1, value: 10 },
1: { key: 2, value: 20 },
2: { key: 3, value: 30 }
};
The arrMap() method creates a new array populated with the results of calling a provided function on every element in the calling array.
arrMapcalls a provided callbackFn function once for each element in an array, in order, and constructs a new array from the results. callbackFn is invoked only for indexes of the array which have assigned values (including undefined).It is not called for missing elements of the array; that is: