Learn TypeScript 3 by Building Web Applications

Implementing the loadMediaCollection method

Persisting data is nice but, of course, it's even nicer if it can be retrieved later.

Let's implement the load method as follows:

loadMediaCollection(identifier: string): Promise<MediaCollection<T>> { 
    console.log(`Trying to load media collection with the following     identifier: ${identifier}`); 
    return new Promise<MediaCollection<T>>((resolve, reject) => { 
        this._store.getItem(identifier) 
            .then(value => { 
                console.log("Found the collection: ", value); 
 
                const retrievedCollection =                 plainToClassFromExist<MediaCollection<T>,                 any>(new MediaCollection<T>(this._type), value); 
 
                console.log("Retrieved collection: ",  retrievedCollection); resolve(retrievedCollection); }) .catch(err => { reject(err); // let the ...