- What does this line do:
@HostBinding('class.valid') isValid;Binds a host element property (here, the CSS class valid) to a directive/component property (isValid).
- What would be a good use for NgZone service?
The most common use of this service is to optimize performance when starting a work consisting of one or more asynchronous tasks that don't require UI updates or error handling to be handled by Angular. Such tasks can be kicked off via runOutsideAngular and if needed, these tasks can reenter the Angular zone via run.
- Why would you use renderer methods instead of using native element methods?
You are not sure what the context you are doing the rendering. You might be assuming the browser compilation and native DOM methods to be available but that might not be the case. It is better to be safe and let Angular handle the manupulation for elements.