Question

When is the constructor automatically called in Angular component classes?

a) After ngOnInit
b) During object creation
c) After ngOnChanges
d) When DOM elements are manipulated

Answer 1

In Angular, the constructor of a component is automatically called when an instance of the component is created. Therefore the correct option is b) During object creation

Step-by-step explanation:

In Angular, the constructor of a component class is automatically called during the object creation phase. When an instance of a component is created, the constructor is invoked as part of the initialization process. It is the first method executed before any lifecycle hooks like ngOnInit or ngOnChanges.

The constructor serves to initialize the component, set up dependencies, and perform any necessary setup tasks required for the component's functionality. It's essential to note that the constructor is called once, and it's primarily used for dependency injection and initializing class properties.

Unlike ngOnInit, which is part of the lifecycle hook sequence and is invoked after Angular has set up the component's input properties, the constructor is called at the very instantiation of the component. This timing ensures that necessary initialization tasks are executed right from the start of the component's lifecycle.

Understanding when the constructor is invoked is crucial for proper initialization of Angular components and ensures that essential setup processes occur at the right stage of the component's lifecycle.

Therefore the correct option is b) During object creation