Question

What does the "delete" keyword in JavaScript do?

A. Removes an element from an array and shifts all elements to the left.
B. Sets an element to null in an array.
C. Throws an error and does not affect the array.
D. Deletes the entire array.

Answer 1

The 'delete' keyword in JavaScript is used to remove a property from an object, array element or to delete a variable. It does not shift array elements and instead leaves an empty space in the array. The 'delete' keyword sets the value of the deleted property to 'undefined'.

Step-by-step explanation:

The 'delete' keyword in JavaScript is used to remove a property from an object, array element or to delete a variable. It does not shift array elements and instead leaves an empty space in the array. The 'delete' keyword sets the value of the deleted property to 'undefined'.

For example, consider an array let fruits = ['apple', 'banana', 'orange'];. If we use the 'delete' keyword to remove an element at index 1 like this: delete fruits[1];, the value at index 1 will become 'undefined', but the length of the array will remain the same. The resulting array will be ['apple', undefined, 'orange'].