Angular Reactive form validation
问题 I'm working with a Reactive form and I have noticed in some tutorials they do the following: HTML . . <input type="text" formControlName="firstName" required> . . TS . . firstName: ['', Validators.required] . . QUESTION: Why do I need to specify "required" in the HTML if I just do it in the TS file it works fine? 回答1: Actually, Angular mention something about that here: Caution: Use these HTML5 validation attributes in combination with the built-in validators provided by Angular's reactive