Sometimes we need to work with every single Control is a form. Here's how it can be done:

function flattenControls(form: AbstractControl): AbstractControl[] {
      let extracted: AbstractControl[] = [ form ];
      if (form instanceof FormArray || form instanceof FormGroup) {
        const children = Object.values(form.controls).map(flattenControls);
        extracted = extracted.concat(...children);
      }
      return extracted;
    }
    

For examples use:

// returns all dirty abstract controls
    extractControls(form).filter((control) => control.dirty);
    
    // mark all controls as touched
    extractControls(form).forEach((control) => 
        control.markAsTouched({ onlySelf: true }));
    

Links

• https://angular.io/guide/reactive-forms