Error in a method exported from a module with Typescript

Question

I am trying to export a specific class of a module, so far so it is all right. I declared my class as Abstract not to need initialize it with the new, but when trying to use the function "getaway()" the compiler returns me the following error:

TS2339: Property 'getItem' does not exist on type 'typeof Webstorage'

MODULUS:

interface IStorage {
    setItem(key : string, value: any) : void;
    getItem(key : string) : any;
    getItem(key : string) : any;
}

export abstract class WebLocalStorage implements IStorage {
    public setItem(key : string, value : any) { 
        localStorage.setItem(key, value);
    }

    public getItem(key : string) : any { 
        localStorage.getItem(key);
    }
}

export abstract class WebStorage implements IStorage {
    public setItem(key : string, value : any) { 
        sessionStorage.setItem(key, value);
    }

    public getItem(key : string) : any { 
        sessionStorage.getItem(key);
    }

}

PLACE WHERE THE MODULE IS BEING IMPORTED:

import { WebStorage } from '../../HTMLAPIS/WebStorageAPI';

export default class FilterData {
    private readonly _typingValue: HTMLInputElement;
    private readonly _containerMain: HTMLElement;
    private readonly _listboxMain: HTMLElement;
    private readonly _listboxSecondary: HTMLElement;

    constructor(public typingValue: HTMLInputElement, public containerMain : HTMLElement, public listboxMain : HTMLElement,  public listboxSecondary : HTMLElement) {
        this._typingValue      = typingValue;
        this._containerMain    = containerMain;
        this._listboxMain      = listboxMain;
        this._listboxSecondary = listboxSecondary;
    }

    public initComponent() {
        this.keypress();
    }

    private keypress() {
        this._typingValue.addEventListener('keypress', (e) => {
            console.log(WebStorage.getItem('shopkeepers_names'));
        });
    }

    searchData() {

    }
}

Answer 1

But abstract doesn’t mean you don’t need to use new, Abstract means that this class cannot be used directly and must be implemented by another class.

To use a method without creating an object, what you need is static.

class WebStorage implements IStorage {
    public static setItem(key : string, value : any) { 
        sessionStorage.setItem(key, value);
    }

    public static getItem(key : string) : string { 
        return sessionStorage.getItem(key);
    }
}

In note: sessionStorage only stores strings. You can even pass a numeric, but this numeric will be converted before it is stored.