A utility to assist in creating Angular forms through Classes using TypeScript annotations.

First the definitions in the tsconfig.json file must be updated:

{
    "compilerOptions":{
		...
		"emitDecoratorMetadata": true,
	    "experimentalDecorators": true
	}
    
}

Obs: The model must be initialized with default values to perform the mapping and build the JavaScript models.

Now we can define a template, and use the annotations available for form configuration:

import { NgFormValidators } from 'ng-form-decorators';
class User {
	name: string = '';
	@NgFormValidators([Validators.required, Validators.max(45)])
	idade: number = null;
}

Use NgFormGroup to define a FormGroup as an attribute of another FormGroup through the building model.

import { NgFormValidators, NgFormGroup } from 'ng-form-decorators';
class  Home {
	@NgFormValidators([Validators.required])
	number:  number  =  null;
	street:  string  =  null;
	@NgFormGroup()
	user:  User;
}

At the end of the definitions, define a variable in the component to represent FormGroup and annotate it with NgFormModel defining the authoring template, and then a form will be built and injected into the variable.

import { NgFormModel } from 'ng-form-decorators';
import { Home } from './models/home.model.ts';
export  class  AppComponent  {

	@NgFormModel(Home)
	formHome:  FormGroup;
}