Angular Directives
Definition of Angular Directives
Angular Directives are classes that add behavior to elements in your Angular applications. Directives are used to manipulate the DOM in various ways, allowing you to create reusable components and customize the behavior of elements in your templates.
Types of Angular Directives
Component Directives:
Definition: A directive with a template. Components are essentially directives with a view. They encapsulate the HTML, CSS, and logic in a single unit.
Use Case: Used to create custom UI elements with their own views and behavior.
Example
Structural Directives:
Definition: Directives that change the DOM layout by adding or removing elements. They are prefixed with an asterisk (*) in the template.
Use Cases:
*ngIf: Conditionally includes a template based on the value of an expression
*ngFor: Iterates over a list of items to render a template for each item
Example
Attribute Directives:
Definition: Directives that change the appearance or behavior of an element, component, or another directive. They do not change the DOM layout.
Use Cases:
ngClass: Dynamically add or remove CSS classes
ngStyle: Dynamically set inline styles
Example
Use Cases of Angular Directives
Component Directives are used to build reusable UI components that encapsulate their own logic and style, such as buttons, forms, or complex widgets.
Structural Directives are used for controlling the visibility and layout of elements based on application state, such as showing elements conditionally or rendering lists.
Attribute Directives are used to dynamically change the appearance or behavior of elements, such as applying styles or toggling CSS classes.
Code Snippets and Examples
Conditional Rendering with
*ngIf:
Looping with
*ngFor
Dynamic Class Binding with
ngClass
Dynamic Style Binding with
ngStyle
References
Angular Directives Documentation
Angular Structural Directives
Angular Attribute Directives
Angular - Introduction to the Angular docs