JS Interview 36: Can you add a new property to the JS array?

Does the new array property affect its length? Is such an assignment valid at all?

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

JavaScript arrays are used to store values in an orderly fashion. Normally, to add a new element, you should use the built-in push() function.

But, in JS, all arrays are objects in the first place. Which means you can add new fields to them.

The assignment arr.greeting = 'Hello, world!' wont raise any errors and is perfectly fine from the language standpoint.

Once its executed, the array will have an extra property greeting.

The length of an array wont change as Hello, world! isnt considered one of the elements of the array.

ANSWER: the length of an array wont change and will remain equal to 4. The second console.log prints out Hello, world! to the screen.

Learn Full-Stack JavaScript