TypeScript class to JSON

Question

I have a class array where the class looks like:

class Tag{
    select: string;
    search: string;
}

I want to convert it to JSON where it'll probably look like [{select: "blah", search: "bleh"}, {...}, {...}].

Is this possible? Because from the Angular 2 tutorial you can do the opposite with the line:

.map((r: Response) => r.json().data as Hero[]);

Answer 1

You can add a toJSON() function in your class. This function gets called automatically when JSON.stringify() is called on your class instance

class Person{
  constructor(readonly name){}

  toJSON(){
    return {
      firstName: this.name
    }
  }
}

Now if you console.log you class instance using JSON.stringify you will see this result

const person = new Person("Tom"); console.log(JSON.stringify(person));

Output

{
  firstName: "Tom"
}

Answer 2

You can convert javascript objects into json strings using JSON.stringify() Since classes and instances of the classes are objects in javascript you can stringify them as well