Updating an object in the ngrx/store

Question

I\'m using @ngrx/store for an Angular 2 app.

My store holds a list of say, Book objects. I want to update a field in one of those objects. I also happ

Answer 1

One way to accomplish this is a utility/helper method to make a new book from. You could give it an existing book and the subset of properties you want to add to a new book (using Partial in typeScript if you want type safety).

createNewBook(oldBook: Book, newProps: Partial): Book {
    const newBook = new Book(); 
    for(const prop in oldBook) {
        if(newProps[prop]) {
            newBook[prop]=newProps[prop];
        } else {
            newBook[prop]=oldBook[prop];
        }
    }
    return newBook 
}

You could call it via newBook = createNewBook(new Book(), {title: 'first foo, then bar'}); and use this newBook to update your store.