Angular 2: Iterate over reactive form controls

Question

I would like to markAsDirty all the controls inside of a FormGroup.

Answer 1

Based on @Keenan Diggs answer I wrote a generic function to traverse a flat or nested form, which accepts an operation to be performed against each form control:

export function traverseForm(
    form: FormGroup | FormArray, 
    fn: ((c: AbstractControl, name: string, path: string) => void),
    initialPath: string = '') {
  Object.keys(form.controls).forEach((key: string) => {
    const abstractControl = form.controls[key];
    const path = initialPath ? (initialPath + '.' + key) : key;
    fn(abstractControl, key, path);
    if (abstractControl instanceof FormGroup || abstractControl instanceof FormArray) {
        traverseForm(abstractControl, fn, path);
    }
  });
} 

To be used like this:

const markAsDirty = (ctrl: AbstractControl) => {
   if (!(abstractControl instanceof FormGroup) && !(abstractControl instanceof FormArray)) {
      abstractControl.markAsDirty();
   }
}
traverseForm(form, markAsDirty);