Learn TypeScript 3 by Building Web Applications

Implementing the saveMediaCollection method

Now we know everything we need to serialize our media collections!

Go ahead and rewrite the saveMediaCollection method as follows:

saveMediaCollection(collection: Readonly<MediaCollection<T>>): Promise<void> { // 1 
    return new Promise<void>((resolve, reject) => { // 2 
        if (!collection) { // 3 
            reject(new Error("The list cannot be null or             undefined!")); 
        } 
 
        console.log(`Saving media collection with the following name         ${collection.name}`); 
 
        const serializedVersion = classToPlain(collection, {         excludePrefixes: ["_"] }); // 4 
        console.log("Serialized version: ", serializedVersion); 
 
        this._store.setItem(collection.identifier, serializedVersion)  // 5 .then(value => { // 6 console.log(`Saved the ${collection.name} ...