Function to get control/form value as a signal

control-value-signal.ts

import { computed, type Injector, isSignal, signal, type Signal, untracked } from '@angular/core';
import { toSignal } from '@angular/core/rxjs-interop';
import { AbstractControl } from '@angular/forms';
import { startWith } from 'rxjs';

/**
 * Returns a signal that contains the value of a control (or a form).
 * @param control
 * @param injector
 */
export function getControlValueSignal<T>(control: AbstractControl<T> | Signal<AbstractControl<T> | undefined>, injector: Injector): Signal<T | undefined> {
  const valueChanges = computed(() => {
    const ctrl = isSignal(control) ? control() : control;
    if (!ctrl) {
      return signal(undefined);
    }

    return untracked(() => toSignal(
      ctrl.valueChanges.pipe(startWith(ctrl.value)),
      {
        injector,
        initialValue: undefined,
      },
    ));
  });

  return computed(() => valueChanges()());
}

Nice, Thanks for sharing