Angular Interview Question Set 1
Categories: Angular
What is Angular? Why was it introduced?
Angular was introduced to create Single Page applications. This framework brings structure and consistency to web applications and provides excellent scalability and maintainability.
Angular is an open-source, JavaScript framework wholly written in TypeScript. It uses HTML's syntax to express your application's components clearly.
What is TypeScript?
TypeScript is a superset of JavaScript that offers excellent consistency. It is highly recommended, as it provides some syntactic sugar and makes the code base more comfortable to understand and maintain. Ultimately, TypeScript code compiles down to JavaScript that can run efficiently in any environment.
What is data binding? Which type of data binding does Angular deploy?
Data binding is a phenomenon that allows any internet user to manipulate Web page elements using a Web browser. It uses dynamic HTML and does not require complex scripting or programming. We use data binding in web pages that contain interactive components such as forms, calculators, tutorials, and games. Incremental display of a webpage makes data binding convenient when pages have an enormous amount of data.
What are Single Page Applications (SPA)?
Single-page applications are web applications that load once with new features just being mere additions to the user interface. It does not load new HTML pages to display the new page's content, instead generated dynamically. This is made possible through JavaScript's ability to manipulate the DOM elements on the existing page itself. A SPA approach is faster, thus providing a seamless user experience.
What are decorators in Angular?
Decorators are a design pattern or functions that define how Angular features work. They are used to make prior modifications to a class, service, or filter. Angular supports four types of decorators, they are:
1. Class Decorators
2. Property Decorators
3. Method Decorators
4. Parameter Decorators
Mention some advantages of Angular.
Some of the common advantages of Angular are -
1. MVC architecture - Angular is a full-fledged MVC framework. It provides a firm opinion on how the application should be structured. It also offers bi-directional data flow and updates the real DOM.
2. Modules: Angular consists of different design patterns like components, directives, pipes, and services, which help in the smooth creation of applications.
3. Dependency injection: Components dependent on other components can be easily worked around using this feature.
What are Templates in Angular?
Angular Templates are written with HTML that contains Angular-specific elements and attributes. In combination with the model and controller's information, these templates are further rendered to provide a dynamic view to the user.
What are Annotations in Angular?
Annotations in Angular are used for creating an annotation array. They are the metadata set on the class that is used to reflect the Metadata library.
What are Directives in Angular?
Directives are attributes that allow the user to write new HTML syntax specific to their applications. They execute whenever the Angular compiler finds them in the DOM. Angular supports three types of directives.
1. Component Directives
2. Structural Directives
3. Attribute Directives