Angular

Create a service wrapper for the browser window, localstorage. The service should implement CRUD $($create read update delete$)$ actions.

Requirements

Implement a Localstorageservice template and logic that contains following methods:

add, which:

accepts two parameters: key and value, of type string:

adds a new item to the localstorage under the given key, only if key doesn't exist already.

returns a Boolean value stating whether the new entry has been added $($true$)$ or not $($false$).$

update, which:

accepts two parameters: key and value, of type string:

changes the value stored under the provided key:

returns a string representing the value that has been replaced with the update;

o$.$ returns nu$11$ if the developer is trying to update a nonexistent value.

remove, which

$$ accepts one parameter: key, of type string:

removes the value specified by the key from the

localstorage: