Recall & Review
beginner
What is the first lifecycle hook called when an Angular component is created?
The first lifecycle hook called is ngOnChanges if the component has input properties. Otherwise, ngOnInit is called next.
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intermediate
Order these Angular lifecycle hooks in the sequence they are called during component creation: ngOnInit, ngOnChanges, ngDoCheck.
The order is: <br>1. ngOnChanges (called when input properties change)<br>2. ngOnInit (called once after first ngOnChanges)<br>3. ngDoCheck (called after ngOnChanges and ngOnInit for custom change detection)
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beginner
What lifecycle hook is called just before Angular destroys a component?
The ngOnDestroy hook is called just before Angular removes the component from the DOM. It is used to clean up resources like subscriptions.
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intermediate
Explain the purpose of ngAfterViewInit in Angular lifecycle.
ngAfterViewInit runs after Angular initializes the component's views and child views. It is useful to access or manipulate the DOM elements after they are rendered.
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advanced
Which lifecycle hooks run every time Angular runs change detection?
The hooks ngOnChanges (if inputs changed) and ngDoCheck run every change detection cycle. They help detect and respond to data changes.
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Which lifecycle hook is called only once after the first ngOnChanges?
✗ Incorrect
ngOnInit runs once after the first ngOnChanges to initialize the component.
When is ngOnDestroy called in Angular?
✗ Incorrect
ngOnDestroy is called just before Angular removes the component to clean up.
Which hook allows you to act after the component's child views are initialized?
✗ Incorrect
ngAfterViewInit runs after the component's views and child views are fully initialized.
What triggers ngOnChanges to run?
✗ Incorrect
ngOnChanges runs only when input properties receive new values.
Which lifecycle hook is best for custom change detection logic?
✗ Incorrect
ngDoCheck allows you to implement custom change detection beyond Angular's default.
Describe the order of Angular lifecycle hooks from component creation to destruction.
Think about what happens when a component starts, updates, and ends.
You got /5 concepts.
Explain when and why you would use ngOnDestroy in an Angular component.
Consider what happens when a component is removed from the page.
You got /4 concepts.