EN
RU
ES
ZH
FR
DE
PT
AR
HI
Why Does This Question Blow Up Stack Overflow (and Your Mind)?
\nYou're writing your first Angular project. You create a component, put the @Component decorator on it — everything works. Then you see @Directive in someone else's code and think: "Why? Isn't it the same thing?". Spoiler: no, it's not the same thing. But confusion arises in 90% of beginners.
The question "@Directive vs @Component in Angular" has thousands of views on Stack Overflow for a reason. Let's figure out once and for all what the difference is, when to use what, and how not to embarrass yourself in an interview. Let's go!
\n\nWhat is @Component? (Spoiler: It's Also @Directive)
\nFirst — a revelation. @Component is a subtype of @Directive. Yes, you heard that right. Any component in Angular is a directive. But with one important difference: a component has a template.
The @Component decorator inherits everything from @Directive and adds its own "feature" — the ability to render HTML. If a directive is "behavior," then a component is "behavior + a piece of the interface."
Example of a Simple Component in TypeScript
\nimport { Component } from '@angular/core';\n\n@Component({\n selector: 'app-hello',\n template: `<h1>Hello, {{name}}!</h1>`,\n styles: ['h1 { color: blue; }']\n})\nexport class HelloComponent {\n name: string = 'World';\n}\nHere, HelloComponent is a full-fledged component. It has its own template, styles, and logic. It can be used in another template as <app-hello></app-hello>.
What is @Directive? (Pure Behavior)
\nA directive is a class with the @Directive decorator that changes the behavior or appearance of an existing DOM element. A directive does not have its own template. It does not create a new element — it "attaches" itself to an existing one.
In Angular, there are three types of directives:
\n- \n
- Components (yes, they are also directives) — with a template. \n
- Structural directives — change the DOM structure (
*ngIf,*ngFor). \n - Attribute directives — change the appearance or behavior of an element (
ngClass,ngStyle). \n
Example of an Attribute Directive in TypeScript
\nimport { Directive, ElementRef, HostListener } from '@angular/core';\n\n@Directive({\n selector: '[appHighlight]'\n})\nexport class HighlightDirective {\n constructor(private el: ElementRef) {}\n\n @HostListener('mouseenter') onMouseEnter() {\n this.el.nativeElement.style.backgroundColor = 'yellow';\n }\n\n @HostListener('mouseleave') onMouseLeave() {\n this.el.nativeElement.style.backgroundColor = null;\n }\n}\nThis directive highlights the element in yellow on mouse hover. It does not create a new DOM node — it "modifies" the existing one. It is used like this: <div appHighlight>Hover over me</div>.
Key Differences: @Directive vs @Component
\nLet's break it down. Here is a table that will help you remember the difference once and for all:
\n\n| Characteristic | \n@Component | \n@Directive | \n
|---|---|---|
| Has a template | \n✅ Yes, required | \n❌ No | \n
| Creates a new DOM element | \n✅ Yes (via selector) | \n❌ No (applied to existing one) | \n
| Has styles | \n✅ Yes, can be isolated | \n❌
BlogsBook RecommendationsRead also |
