Q: What is runInInjectionContext and when do you need to use it?

**Target Audience:** Developers who use inject() and the signal or RxJS interop APIs and have met NG0203 — explains dependency injection context from first principles. **Difficulty:** Medium > **How to read this doc:** Plain language first, then 📌 Interview term: callouts. Every error message and output below was produced on Angular 22.2.3: components compiled with ngc and run in jsdom, guards, resolvers and interceptors booted with a real appConfig

Question 1

What does the Angular CLI provide?

Accepted Answer

**Target Audience:** Anyone preparing for an Angular interview — no Angular experience needed. **Difficulty:** Easy > **How to read this doc:** Plain language first, then 📌 Interview term: callouts. Everything under "Verified" was produced by running Angular CLI 22.2.3 in a sandbox: ng new, ng generate --dry-run, ng serve, ng build, ng test and ng lint, with the real output quoted. ng add an

Question 2

What is a route resolver and when is it useful?

Accepted Answer

**Target Audience:** Developers comfortable with routes and guards who need to decide how a routed screen gets its data — assumes [route guards](/interview-question/what-are-route-guards-in-angular) basics. **Difficulty:** Medium > **How to read this doc:** Plain language first, then 📌 Interview term: callouts. The timelines and results in sections 5 and 6 come from compiling the examples with ngc on Angular 22.2.3 and navigating with Router.navigateByUrl

Question 3

What are route guards in Angular?

Accepted Answer

**Target Audience:** Developers who have routes working and now need to control who can go where — assumes basic routing knowledge. **Difficulty:** Medium > **How to read this doc:** Plain language first, then 📌 Interview term: callouts. The call order in section 5 is real output from compiling the example with ngc on Angular 22.2.3 and navigating with Router.navigateByUrl; it is not reconstructed from documentation. ## 1. Why This Even Matters — A Story

Question 4

How do functional route guards and lazy loadComponent work in modern Angular?

Accepted Answer

**Target Audience:** Developers using standalone components and lazy routes who want to know exactly what downloads when — assumes you know [route guards](/interview-question/what-are-route-guards-in-angular) and [lazy loading](/interview-question/how-does-routing-and-lazy-loading-work-in-angular). **Difficulty:** Medium to Hard > **How to read this doc:** Plain language first, then 📌 Interview term: callouts. Every "loader called" line below was printed by a real loader function

Question 5

inject() vs constructor injection — when should you use each?

Accepted Answer

**Target Audience:** Developers and tech leads choosing a team convention, and candidates asked "which do you prefer and why?". **Difficulty:** Medium > **How to read this doc:** Ideas are explained in plain language first, then tagged with 📌 Interview term: so you also learn the words an interviewer listens for. This page is the *decision guide*. What each style compiles to, the injection-context rules and the inheritance mechanics are in the sibling question [constructor-based D

Question 6

What are functional Route Guards, and how do they differ from class-based guards?

Accepted Answer

**Target Audience:** Developers maintaining or modernising an existing Angular app — assumes you know what a route guard does (see [route guards](/interview-question/what-are-route-guards-in-angular)). **Difficulty:** Medium > **How to read this doc:** Plain language first, then 📌 Interview term: callouts. Every log and error message in sections 5 and 6 came from compiling the examples with ngc (strict templates) on Angular 22.2.3 and navigating with Router.navi

Question 7

What is the difference between constructor-based DI and the inject() function?

Accepted Answer

**Target Audience:** Developers comfortable with services who want to know what actually happens when Angular builds a class, for example before migrating a codebase. **Difficulty:** Medium > **How to read this doc:** Ideas are explained in plain language first, then tagged with 📌 Interview term: so you also learn the words an interviewer listens for. The compiled factories in section 3 were emitted by ngc 22.2.3 from the code shown, and every error message below was

Question 8

How does routing and lazy loading work in Angular?

Accepted Answer

**Target Audience:** Anyone preparing for an Angular interview — assumes you know what a component is, no router experience needed. **Difficulty:** Easy to Medium > **How to read this doc:** Plain language first, then 📌 Interview term: callouts with the vocabulary an interviewer expects. The navigation logs in section 5 were produced by compiling the example with ngc on Angular 22.2.3 and driving it with Router.navigateByUrl; the bundle sizes in section 6

Question 9

What is runInInjectionContext and when do you need to use it?

Accepted Answer

**Target Audience:** Developers who use inject() and the signal or RxJS interop APIs and have met NG0203 — explains dependency injection context from first principles. **Difficulty:** Medium > **How to read this doc:** Plain language first, then 📌 Interview term: callouts. Every error message and output below was produced on Angular 22.2.3: components compiled with ngc and run in jsdom, guards, resolvers and interceptors booted with a real appConfig

ANGULARDECODED.

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