typescript, How do I pass an object to a constructor of class for instantiation

Question

I have an array object data get from backend api. like:

[
 {name: 'react', age: 4},
 {name: 'angular', age: 4},
 ...
 {name: 'rxjs', age: 2}
]

And I definite a class and an interface, like this:

interface IBook {
  name: string;
  age: number;
}

class Book{
  book: IBook;

  constructor(book: IBook) {
    this.book = book;
  }

  //I can definite some method here: 

  getFullName() {
    return this.book.firstName + ' ' + this.book.lastName;
  }

  isValid() {
    return book.name.length > 0;
  }

}

//when get the data
const dataModels = datas.map(data => {
  return new Book(data);
});

so I can encapsulate some data model methods like book.getFullName()

I can use it like this:

const fullname = book.getFullName()

rather than this:

const fullname = book.firstName + ' ' + book.lastName;

Is there a better way to do this? I am not sure my thought is the correct way or not.

The problem is how to convert a js object to ts class model according to a correct way.

Or, just definite the data interface. Is it necessary to convert javascript json data to typescript class model?

-- update --

especially, the nested data. like this:

const datas = [
 {name: 'react', age: 2, tag: [{id: 1}, {id: 2}]}
]

Answer 1

If no methods are needed, just cast your data. Otherwise, you may copy the data to your class.

let datas = [
 {name: 'react', age: 4, extra: { value: 1 }},
 {name: 'angular', age: 4, extra: { value: 2 }},
 {name: 'rxjs', age: 2, extra: { value: 3 }}
]

interface IBook {
  name: string;
  age: number;
}

interface Extra {
    value: number;
}

let books: IBook[] = datas;
console.log(books[0].name); // react

class Book {
    name: string;
    age: number;
    extra: Extra;

    constructor(data: any) {
        for (let key in data) {
            this[key] = data[key];
        }
    }

    getFullName() {
        return this.name;
    }

    isValid() {
        return this.name.length > 0;
    }
}

let books2 = datas.map(book => new Book(book));
console.log(books2[1].getFullName()); // angular
console.dir(books2[0].extra.value); // 1