While creating a Model Driven Template Reactive forms, when I create model object from Form Value. Then model object is loosing its TYPE.
For a Simple Example:
Model Class Book:
export class Book {
public name: string;
public isbn: string;
}
Component:
@Component({
selector: 'app-book',
templateUrl: './book.component.html',
styleUrls: ['./book.component.css']
})
export class BookComponent implements OnInit {
bookFormGroup: FormGroup;
private newBook: Book = new Book();
constructor(private fb: FormBuilder) {
this.bookFormGroup = this.fb.group({
name: new FormControl(''),
isbn: new FormControl('')
});
}
ngOnInit() {
}
addBook() {
console.log('submit');
this.newBook = <Book> this.bookFormGroup.value;
console.log(this.newBook instanceof Book);
console.log(this.newBook);
}
}
HTML:
<form [formGroup]="bookFormGroup" (ngSubmit)="addBook()">
<input type="text" formControlName="name" >
<input type="text" formControlName="isbn" >
<input type="submit" value="Submit">
</form>
In the above example, after filling newBook
instance its converted to normal Object
i.e,
After this.newBook = <Book> this.bookFormGroup.value;
this.newBook instanceof Book
is becoming FALSE
How do I prevent this?
Or is there any better way to achieve this?
Note: I tried with JSON.parse()
but it still same.
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