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Dynamic forms for Angular using Typescript Decorators.

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DynamicForms

A dynamic form generator using Typescript Decorators.

More info in Dynamic Forms.

How to install

The default components use Angular Material. Add with ng add @angular/material. Install the library ng add @guihss/ngx-dynamic-forms.

Example

Annotate the class you want to generate the form.

export class User {
  
  @FormInput({ label: "Name", type: "text" })
  name = 'Bob';
  
  @FormInput({ label: "Password", type: "password"})
  password;
  
  @FormInput({ label: "Email", type: "email"})
  email;
}

Create an observable instance.

export class AppComponent {
  title = 'dynamic-forms-showcase';

  user: Observable<User> = of<User>(new User());
}

Add the dynamic-forms component to your page.

<mat-card>
  <h1> Example form </h1>

  <dynamic-form
    formStyleClass="dynamic-form"
    [objectObservable]="user"
  ></dynamic-form>

</mat-card>

And see the result :D

Example form

The inputs are rendered in the defined order and uses any values in the field as default.

Get form data

You can access the data inserted in the form with.

class AppComponent {
    /* ... */
    @ViewChild(DynamicFormsComponent) dynamicForm: DynamicFormsComponent;
    
    ngAfterViewInit(): void {
    
        let formResult = this.dynamicForm.getResult();
    
    }
}

The result is a json with field names equals to the annotated field. Filled with the form values.

let formResult = {
  name: 'Bob',
  password: 'verysecurepassword',
  email: ''  
}

Defining custom form inputs

With dynamic forms you can use your own components.

ng generate component custom-input

Implement the ConfigurableInput interface.

export class CustomInputComponent implements ConfigurableInput {
  
  formControl = new FormControl();  

  applyArguments(args: any): any {
    /* here you can use the args passed in the annotation 
        to configure your input. */
  }

  getFormControl(): any {
    return this.formControl;
  }
  
}

Use the @CustomInput annotation in your model.

export class User {

  /* ... */

  @CustomInput(CustomInputComponent, {label: "Custom Input", args: {}})
  myCustomInput;

}

The result: Custom Input

Nesting inputs

You can nest inputs with dynamic forms.

export class NestedObject {

  @FormInput({ label: "street", type: "text" })
  street;

  @FormInput({ label: "city", type: "text" })
  city;  
}

export class User {

    /* ... */

    @NestedInput('Address', /* search depth */ 1)
    address = new NestedObject();
}

Result:

Nested Input

The form data are nested too.

let formResult = {
  name: 'Bob',
  password: 'verysecurepassword',
  email: '',
  myCustomInput: '',
  address: {
    street: '',
    city: ''
  } 
}

Showcase

The code has a showcase to help you in development if you want to improve the library.

Run with ng serve.