What are the differences between Array.from() and the spread operator in JavaScript?

Richard W

In JavaScript, bothArray.from() and the spread operator (...) are used to convert iterable objects or array-like objects into real arrays. While they achieve a similar outcome, there are some differences between them: 1. Usage: -Array.from(): -Array.from() is a static method of theArray object. - It is invoked as a function and accepts an iterable or array-like object as its first argument. - Spread Operator (...): - The spread operator is a syntax feature introduced in ES6. - It is used by placing... before an iterable or array-like object. 2. Accepting Arguments: -Array.from(): - Apart from the first argument,Array.from() also accepts two additional optional arguments: a mapping function and athis value to be used within the mapping function. - The mapping function allows you to transform each element of the iterable object during the conversion. - Spread Operator (...): - The spread operator does not accept any additional arguments. - It simply spreads the elements of the iterable or array-like object into a new array. 3. Handling Non-iterable Objects: -Array.from(): - When the provided object is not iterable,Array.from() throws aTypeError. - Spread Operator (...): - The spread operator requires the object to be iterable. - If a non-iterable object is passed, it will throw aTypeError or result in unexpected behavior. 4. Array-Like Objects: -Array.from(): -Array.from() can convert array-like objects, such as thearguments object orNodeList, into real arrays. - It creates a new array, copying the values from the array-like object. - Spread Operator (...): - The spread operator cannot directly convert array-like objects into arrays. - It can only be used with iterables, such as arrays or strings. 5. Support for Iterators and Generators: -Array.from(): -Array.from() can convert objects that implement the iterable protocol, such as arrays or strings, as well as objects that have a custom iterator or generator function. - Spread Operator (...): - The spread operator can only be used with objects that implement the iterable protocol, such as arrays or strings. - It does not work with objects that have a custom iterator or generator function. 6. Browser Compatibility: -Array.from(): -Array.from() is supported in most modern browsers, including Chrome, Firefox, Safari, and Edge. However, it may not be available in older versions of some browsers. - Spread Operator (...): - The spread operator is also widely supported in modern browsers, including Chrome, Firefox, Safari, and Edge. However, it may not work in older versions of some browsers. Choose betweenArray.from() and the spread operator based on your specific requirements and browser compatibility. If you need to convert non-iterable or array-like objects, or if you require the use of a mapping function,Array.from() is more suitable. On the other hand, if you are working with iterables like arrays or strings, the spread operator provides a more concise and convenient syntax.