angular 5 template forms detect change of form validity status

Question

are reactive forms the way to go in order to have a component that can listen for changes in the validity status of the form it contains and execute some compoment\'s method

Answer 1

You can do something like this do detect a validity change and execute a method based on whether the form is VALID or INVALID.

this.myForm.statusChanges
  .subscribe(val => this.onFormValidation(val));

onFormValidation(validity: string) {
  switch (validity) {
    case "VALID":
      // do 'form valid' action
      break;
    case "INVALID":
      // do 'form invalid' action
      break;
  }
}