Developing JSON objects with Typescript

What is the best approach to generate and store an array of JSON objects when a new item is added? The issue I am currently facing is:

  1. Is it necessary to create a class object before saving JSON objects, or can they be saved directly?
  2. What method should be used to determine if a specific item already exists in the array?

Answer №1

Storing JSON data in variables of class any is common practice, but adding typing to these objects is recommended. One approach is to create a static method called fromJson in model classes to instantiate objects from JSON data. Here's an example:

class User {

    public firstname: string;
    public lastname: string;
    public age: number;

    constructor() {
    }

    public static fromJson(userJson: any): User {
        var user = new User();

        this.firstname = userJson.firstname;
        this.lastname = userJson.lastname;
        this.age = userJson.age;

        return user;
    }
}

If a property in your class is another class, you can also create a fromJson method for that class and include it in the main fromJson method like this:

class User {

    public firstname: string;
    public lastname: string;
    public status: Status;

    constructor() {
    }

    public static fromJson(userJson: any): User {
        var user = new User();

        this.firstname = userJson.firstname;
        this.lastname = userJson.lastname;
        this.status = Status.fromJson(userJson.status);

        return user;
    }
}

I hope this explanation is helpful!

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