Structural directives

Last reviewed May 28, 2026 Content v20260528

Track mode

client_angular

Means

In-browser Angular TS

Reading

~1 min

Level

intermediate

This lesson

This lesson teaches Structural directives: the concepts, APIs, and habits you need before advancing in Angular.

Directives extend HTML in 1.x—read link/compile when debugging DOM behavior.

You will apply Structural directives in contexts like: Large Angular codebases, line-of-business apps, and teams standardized on TypeScript everywhere.

Write TypeScript with decorators, click Run—Angular 19 loads from CDN, use the Ng global and mountApp(Component) with selector app-root; printOutput feeds the terminal.

When you can explain the previous lesson's ideas without copying starter code.

*ngFor and *ngIf control DOM structure; always track by stable keys.

Import [Ng.CommonModule] in standalone @Component when using *ngIf or *ngFor.

Important interview questions and answers

Q: Why does this matter?
A: *ngFor and *ngIf control DOM structure; always track by stable keys.

Self-check

Summarize Structural directives in one sentence.
What would you try next in the playground?

Challenge