Preloading strategies in Angular - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the purpose of preloading strategies in Angular routing?

Preloading strategies help load lazy-loaded modules in the background after the app starts, improving user experience by reducing wait times when navigating.

beginner

Name the two built-in preloading strategies Angular provides.

Angular provides NoPreloading (default, no modules preloaded) and PreloadAllModules (all lazy modules preload after app start).

beginner

How do you enable the PreloadAllModules strategy in Angular?

In the RouterModule.forRoot() method, pass { preloadingStrategy: PreloadAllModules } as the second argument.

intermediate

What is a custom preloading strategy in Angular?

A custom preloading strategy is a user-defined service implementing the PreloadingStrategy interface to control which modules preload based on custom logic.

intermediate

Why might you choose a custom preloading strategy over the built-in ones?

To preload only specific modules based on conditions like user roles, network speed, or app state, optimizing performance and resource use.

Which Angular preloading strategy loads all lazy modules immediately after app start?

A CustomPreloading

B NoPreloading

C PreloadAllModules

D LazyLoadingOnly

PreloadAllModules loads all lazy modules in the background after the app starts, improving navigation speed.

What is the default preloading strategy in Angular routing?

A NoPreloading

B PreloadAllModules

C CustomPreloading

D EagerLoading

NoPreloading is the default, meaning lazy modules load only when the user navigates to them.

How do you specify a preloading strategy in Angular routing configuration?

A In the RouterModule.forRoot() options

B In the module imports array

C In the component decorator

D In the main.ts file

You set the preloading strategy by passing { preloadingStrategy: ... } to RouterModule.forRoot().

What interface must a custom preloading strategy implement?

A OnInit

B Resolve

C CanActivate

D PreloadingStrategy

Custom preloading strategies implement the PreloadingStrategy interface to define preload behavior.

Which scenario best fits using a custom preloading strategy?

A Preload all modules regardless of conditions

B Preload modules based on user permissions

C Load modules only on navigation

D Never preload any modules

Custom strategies allow preloading modules selectively, such as based on user permissions or network conditions.

Explain what preloading strategies are in Angular and why they matter.

Think about how apps load parts in the background to be ready faster.

Describe how to implement a custom preloading strategy in Angular.

Focus on the interface and where to configure it.