Aurelia Interview Questions and Answers: Aurelia is a modern JavaScript framework that is gaining popularity among developers for its simplicity and flexibility. As the demand for Aurelia developers is increasing, it is important for job seekers to prepare well for their interviews. To help you out, we have compiled a list of the Top 100 Aurelia Interview Questions and Answers, including the latest Aurelia Interview Questions, Aurelia Technical Interview Questions, and Aurelia Interview Questions for Freshers.
★★ Latest Technical Interview Questions ★★
Aurelia Technical Interview Questions
These Latest Aurelia Interview Questions cover a wide range of topics, including Aurelia architecture, data binding, components, routing, and more. By practicing these questions, you can gain confidence and increase your chances of landing your dream job in the Aurelia development field.
Top 100 Aurelia Interview Questions and Answers 2023
1. What is Aurelia?
Ans: Aurelia is a modern, open-source JavaScript framework that allows developers to create complex, dynamic, and scalable web applications.
2. What are the key features of Aurelia?
Ans: Some of the key features of Aurelia include:
- Modern Architecture (MVVM)
- Two-Way Databinding
- Extensible HTML
- Routing & UI Composition
- ES6/ ES7 transpiled support
- Fully covered testing support
- Broad Language Support
- Advanced client side router via Durandeljs
- Jspm for package management
3. What are the advantages of using Aurelia?
Ans: Aurelia offers many advantages, such as a clean and modular architecture, an easy-to-use CLI, excellent documentation and support, and a powerful set of features for building complex web applications.
4. Explain Component Lifecycle of Aurelia
Components in the Ionic framework follow a specific lifecycle, and there are several methods available to implement on the view-model to connect with this lifecycle.
- Constructor (): This method is used to initialize an object created with a class. The view-model’s constructor is called first.
- Created (owningView: View, myView: View): If the view-model implements the created callback, it is invoked next. At this point in time, the view has also been created and both the view-model and the view are connected to their controller. The created callback will receive the instance of the “owningView”. This is the view that the component is declared inside of. If the component itself has a view, this will be passed second.
- Attached (): The component is attached to the DOM. If the view-model has an attached callback, it will be invoked at this time.
- Detached (): This method is called when the View is detached from the DOM. The component may be removed from the DOM. If/When this happens, and if the view-model has a detached callback, this is when it will be invoked.
- Bind (bindingContext: Object, overrideContext: Object): This method happens after binding occurs but before the DOM attachment. This is where the Databinding engine binds the contents of the View.
- Unbind (): After a component is detached, it’s usually unbound. If your view-model has the unbind callback, it will be invoked during this process.
5. What is the Aurelia CLI?
Ans: The Aurelia CLI is a command-line interface tool that allows developers to create and manage Aurelia projects. It provides a set of tools and templates for generating components, services, and other resources.
6. What is the role of Aurelia’s templating system?
Ans: Aurelia’s templating system allows developers to create reusable components and views using HTML and JavaScript. It provides powerful features like data binding, custom elements, and attribute binding.
7. What is the difference between one-way and two-way data binding in Aurelia?
Ans: One-way data binding is a mechanism in Aurelia where data flows in one direction, from the model to the view. Two-way data binding allows data to flow in both directions, between the model and the view.
8. What use of debounce in Aurelia?
Ans: The Aurelia framework includes the debounce binding behavior, which serves as another rate-limiting mechanism that delays the update of bindings until a defined interval has elapsed without any changes. One common scenario where debounce binding is useful is in a search input that triggers automatic searching.
9. What is the role of dependency injection in Aurelia?
Ans: Dependency injection is a key feature of Aurelia that allows developers to manage dependencies and modularize their code. It provides a mechanism for creating, managing, and injecting dependencies into components and services.
10. What is the purpose of Aurelia’s router?
Ans: Aurelia’s router is a powerful feature that allows developers to create and manage navigation within their applications. It provides a way to define routes, handle navigation events, and manage application state.
11. What is the difference between global and local styles in Aurelia?
Ans: Global styles are applied to the entire application, while local styles are applied to specific components or views. Local styles take precedence over global styles.
12. What is the role of event aggregation in Aurelia?
Ans: Event aggregation is a feature in Aurelia that allows developers to communicate between different components in their application. It provides a way to publish and subscribe to events, and allows components to communicate without having direct knowledge of each other.
13. What is the Aurelia plugin ecosystem?
Ans: The Aurelia plugin ecosystem is a collection of third-party plugins and extensions that extend the functionality of the Aurelia framework. These plugins provide additional features like data visualization, authentication, and UI components.
14. What is the difference between custom elements and attributes in Aurelia?
Ans: Custom elements are standalone components that can be used in HTML like any other standard HTML element, while attributes are used to modify the behavior or appearance of existing HTML elements.
15. How does Aurelia handle error handling and debugging?
Ans: Aurelia provides robust error handling and debugging features, including detailed error messages, stack traces, and a powerful debugging tool called the Aurelia Inspector.
16. What is the difference between a view and a view model in Aurelia?
Ans: A view is the HTML template that defines the layout and structure of a component, while a view model is the JavaScript code that provides the logic and data for the component.
17. What is the Aurelia plugin registry?
Ans: The Aurelia plugin registry is a central repository for Aurelia plugins and extensions. It allows developers to browse and discover new plugins, as well as publish their own plugins for others to use.
18. How does Aurelia handle browser compatibility?
Ans: Aurelia is designed to work across all modern browsers, including Internet Explorer 11. It uses polyfills and shims to provide support for features that may not be available in older browsers.
19. What is the Aurelia framework lifecycle?
Ans: The Aurelia framework lifecycle consists of several stages, including binding, attaching, detaching, and unbinding. These stages correspond to differe nt points in the component’s lifecycle and provide opportunities for performing tasks like initialization and cleanup.
20. What is the role of the Aurelia binding engine?
Ans: The Aurelia binding engine is responsible for managing data binding between the view and the view model. It provides a mechanism for updating the view in response to changes in the model, as well as updating the model in response to user input.
21. What is the Aurelia composition model?
Ans: The Aurelia composition model is a powerful feature that allows developers to dynamically compose views and components at runtime. It provides a way to create complex UIs that are highly flexible and extensible.
22. What is the role of the Aurelia DI container?
Ans: The Aurelia DI container is responsible for managing dependencies and creating instances of components and services. It provides a way to organize and modularize code, and allows for easy unit testing.
23. What is the Aurelia UX library?
Ans: The Aurelia UX library is a collection of UI components and styles designed to work seamlessly with the Aurelia framework. It provides a set of pre-built UI elements that can be used to create beautiful and responsive user interfaces.
24. What is the difference between the Aurelia CLI and the Aurelia webpack plugin?
Ans: The Aurelia CLI is a command-line tool for managing Aurelia projects, while the Aurelia webpack plugin is a plugin for the webpack build tool that enables developers to build and bundle Aurelia applications.
25. What is the role of the Aurelia event aggregator?
Ans: The Aurelia event aggregator is a powerful feature that allows components to communicate with each other without having direct knowledge of each other. It provides a way to publish and subscribe to events, and allows for highly decoupled and modular code.
26. What is the difference between Aurelia’s attribute and element binding syntax?
Ans: Aurelia’s attribute binding syntax is used to bind data to HTML attributes, while its element binding syntax is used to bind data to custom elements. Both syntaxes allow for two-way data binding.
27. What is the difference between Aurelia’s ref binding and event binding?
Ans: Aurelia’s ref binding is used to reference elements in the DOM, while its event binding is used to handle events like mouse clicks and key presses. Both bindings are important features of Aurelia’s data binding system.
28. How does Aurelia handle lazy loading of components?
Ans: Aurelia provides built-in support for lazy loading of components, which allows developers to defer the loading of components until they are actually needed. This can help improve application performance and reduce startup time.
29. What is the Aurelia HTTP client?
Ans: The Aurelia HTTP client is a powerful feature that provides a simple and consistent way to make HTTP requests from within Aurelia applications. It supports a wide range of HTTP methods and provides features like request and response interception.
30. What is data binding in Aurelia?
- Data binding in Aurelia is a powerful feature that allows developers to bind data from the model to the view, and vice versa.
- Aurelia supports one-way, two-way, and one-time data binding.
31. What is the difference between Aurelia’s singleton and transient dependency injection strategies?
Ans: Aurelia’s singleton strategy creates a single instance of a dependency and shares it across all components that request it, while its transient strategy creates a new instance of the dependency each time it is requested.
32. How does Aurelia handle internationalization and localization?
Ans: Aurelia provides built-in support for internationalization and localization, which allows developers to create applications that can be used in multiple languages and locales. It provides away to manage translations, date formatting, and other localization-related tasks.
33. What is the Aurelia templating engine?
Ans: The Aurelia templating engine is responsible for compiling and rendering views in Aurelia applications. It provides a powerful set of features, including data binding, template directives, and custom element creation.
34. How does Aurelia handle routing?
Ans: Aurelia provides a built-in router that allows developers to create complex navigation paths in their applications. It supports both client-side and server-side routing and provides a way to define routes using a simple and intuitive syntax.
35. What is the role of the Aurelia validation library?
Ans: The Aurelia validation library provides a powerful and flexible way to validate data in Aurelia applications. It supports a wide range of validation rules and provides a way to create custom validation rules as well.
36. What is the Aurelia composition lifecycle?
Ans: The Aurelia composition lifecycle consists of several stages, including activate, candeactivate, deactivate, and canActivate. These stages provide opportunities for performing tasks like loading data, validating inputs, and cleaning up after a component is removed from the DOM.
37. What is Throttle in Aurelia?
Ans: Aurelia’s throttle feature serves as a rate limiter during the binding process, which involves a series of behaviors that enable various scenarios. During this process, the first behavior applied is the throttle binding, which restricts the continuous two-way binding of the view model, as well as the one-way binding of the view when it undergoes updates. The Aurelia framework offers multiple behaviors to facilitate these functionalities.
38. How does one-way binding differ from two-way binding in Aurelia?
| one-way binding | two-way binding |
| One-way binding only updates the target property or element when the source property changes | two-way binding updates both the source and target properties when either one changes |
| One-way binding uses a binding mode of one-way | two-way binding uses a binding mode of two-way |
39. What is the difference between Aurelia’s view model and model?
Ans: Aurelia’s view model represents the data and behavior of a view, while its model represents the data that is being displayed in the view. The view model provides a way to manage the behavior of a view, while the model provides a way to manage the data.
40. What is the role of the Aurelia router pipeline?
Ans: The Aurelia router pipeline provides a way to add middleware to the Aurelia router. Middleware functions can be used to perform tasks like authentication, logging, and error handling.
41. How does Aurelia handle server-side rendering?
Ans: Aurelia provides built-in support for server-side rendering, which allows developers to create applications that can be rendered on the server before being sent to the client. This can help improve application performance and reduce the time required to render the initial view.
42. What are the types of Official Plugins used in Aurelia?
Ans: Different types of Official Plugins used in Aurelia are:
- i18n()
- fetch()
- dialog()
- animatorCSS()
- validation()
- animator-velocity()
- ui-virtualization()
43. What is the Aurelia metadata system?
Ans: The Aurelia metadata system provides a way to associate metadata with classes and functions in an Aurelia application. This metadata can be used by the framework to perform tasks like dependency injection and view composition.
44. What is the Aurelia event bubbling system?
Ans: The Aurelia event bubbling system provides a way to handle events that occur in child elements from parent elements. This allows for highly modular and decoupled code and helps to reduce the amount of code required to manage complex UIs.
45. What is the difference between the @computedFrom and @computed decorators?
| @computedFrom | @computed |
| @computedFrom is used to observe changes in one or more properties and trigger a change in a computed property | @computed is used to define a computed property that depends on one or more other properties |
| @computedFrom can only observe changes in a finite number of properties | @computed can be used with any number of properties |
46. What is the Aurelia testing framework?
Ans: The Aurelia testing framework provides a way to write and run unit tests for Aurelia applications. It supports a wide range of testing scenarios and provides features like dependency injection and test fixtures.
47. What is the difference between the Aurelia binding command and binding behavior?
Ans: Aurelia’s binding command is used to modify the behavior of a data binding, while its binding behavior is used to add new behavior to a data binding.
48. What is the syntax for custom attribute creation in Aurelia?
| <element custom-attribute></element> |
49. What is the syntax for binding to a custom attribute in Aurelia?
| <element custom-attribute.bind=”expression”></element> |
50. What is i18n() plugin?
Ans: i18n() Plugin is used for internalization and localization.
51. What is the Aurelia validation plugin?
- The Aurelia validation plugin is a plugin that provides form validation for Aurelia applications.
- It allows developers to define validation rules for their forms and provides a way to display validation errors.
52. What is the Aurelia event aggregator’s publish/ subscribe pattern?
Ans: The Aurelia event aggregator’s publish/ subscribe pattern allows components to communicate with each other without having direct knowledge of each other. A component can publish an event, and other components that are subscribed to that event will receive it and respond accordingly.
53. What are the types of Standard Plugins used in Aurelia?
Ans: Different types of Standard Plugins used in Aurelia
- Router()
- History()
- eventAggregator()
- defaultResources()
- defaultBindingLanguage()
54. What is the Aurelia custom element lifecycle?
Ans: The Aurelia custom element lifecycle consists of several stages, including created, bind, attached, detached, and unbind. These stages correspond to different points in the element’s lifecycle and provide opportunities for performing tasks like initialization and cleanup.
55. What is the difference between the Aurelia value converter and binding behavior?
Ans: Aurelia’s value converter is used to transform data in a data binding, while its binding behavior is used to add new behavior to a data binding.
56. What is the Aurelia dependency injection container?
Ans: The Aurelia dependency injection container provides a way to manage dependencies in an Aurelia application. It allows developers to specify which objects should be injected into which classes, making it easier to manage complex dependencies.
57. How does Aurelia handle animations?
Ans: Aurelia provides built-in support for animations, which allows developers to add animation effects to their applications using a simple and intuitive syntax. The framework supports a wide range of animation types, including CSS animations, JavaScript animations, and Web Animations API animations.
58. What is the syntax for event binding in Aurelia?
| (event)=”expression” |
59. What is the syntax for conditional rendering in Aurelia?
| <element if.bind=”expression”></element> |
60. What is the syntax for repeat rendering in Aurelia?
| <element repeat.for=”item of items”></element> |
61. What is the Aurelia CLI?
Ans: The Aurelia CLI is a command-line tool that provides a way to create, build, and deploy Aurelia applications. It includes a wide range of features, including automatic code generation, live-reloading, and easy deployment to popular hosting platforms.
62. What is the Aurelia plugin system?
Ans: The Aurelia plugin system provides a way to extend the functionality of the Aurelia framework. Developers can create custom plugins that add new features, components, and behaviors to their applications.
63. What is the Aurelia history API fallback?
Ans: The Aurelia history API fallback provides a way to use the HTML5 history API for client-side routing while falling back to hash-based URLs for older browsers. This allows developers to create applications that work seamlessly across a wide range of devices and browsers.
64. What is the syntax for defining a custom element bindable property in Aurelia?
| @bindable propertyName |
65. What is the syntax for defining a custom element bindable property with options in Aurelia?
| @bindable({ defaultBindingMode: bindingMode.oneTime, defaultValue: ‘default value’ }) propertyName |
66. What is the Aurelia dependency injection hierarchy?
Ans: The Aurelia dependency injection hierarchy allows developers to specify which objects should be injected into which classes, based on their position in the hierarchy. This makes it easier to manage dependencies in complex applications.
67. What is the difference between the Aurelia property and attribute binding?
Ans: Aurelia’s property binding is used to bind a JavaScript property to a DOM element, while its attribute binding is used to bind an HTML attribute to a DOM element.
68. What is the Aurelia behavior instruction?
Ans: The Aurelia behavior instruction provides a way to modify the behavior of a data binding. It can be used to add new behavior to a data binding, modify existing behavior, or even create entirely new behavior.
69. What is the syntax for one-way data binding in Aurelia?
| ${expression} |
70. What is the syntax for two-way data binding in Aurelia?
| ${expression & two-way} |
71. What is the syntax for one-time data binding in Aurelia?
| ${expression & one-time} |
72. What is the Aurelia observer locator?
Ans: The Aurelia observer locator provides a way to locate and manage observers in an Aurelia application. Observers are used to monitor changes to data in a view and update the view accordingly.
73. What is the Aurelia binding expression syntax?
Ans: The Aurelia binding expression syntax provides a way to create complex data bindings in an Aurelia application. It includes a wide range of features, including property accessors, array and object accessors, and function calls.
74. What is the Aurelia binding engine?
- The Aurelia binding engine is a powerful feature that allows developers to create data bindings between the view and the model.
- It provides one-way, two-way, and one-time data binding options.
75. What is the Aurelia dynamic composition system?
Ans: The Aurelia dynamic composition system provides a way to dynamically compose views in an Aurelia application. It allows developers to create complex UIs that can be customized and modified at runtime.
76. What is the difference between a custom element and a custom attribute?
| custom element | custom attribute |
| A custom element is a standalone HTML element with its own view and view model | a custom attribute modifies an existing HTML element with additional behavior. |
| A custom element is defined with the @customElement decorator | custom attribute is defined with the @customAttribute decorator |
77. What is the syntax for custom element creation in Aurelia?
| <custom-element></custom-element> |
78. What is the syntax for binding to a custom element property in Aurelia?
| <custom-element property.bind=”expression”></custom-element> |
79. What is the syntax for two-way binding to a custom element property in Aurelia?
| <custom-element property.bind=”expression & two-way”></custom-element> |
80. What is the syntax for binding to a custom element event in Aurelia?
| <custom-element event.bind=”expression”></custom-element> |
81. What is the difference between @inject and @autoinject decorators?
| @inject | @autoinject |
| used to specify dependencies for a class that will be resolved through the Aurelia dependency injection system | used to automatically inject all dependencies into the constructor of a class |
| more flexible because it allows you to specify individual dependencies | injects all dependencies whether you need them or not |
82. What is dependency injection in Aurelia?
- Dependency injection in Aurelia is a technique for managing dependencies in a web application.
- It allows developers to define dependencies in one place and inject them into any part of
- the application that needs them.
83. What is routing in Aurelia?
- Routing in Aurelia is a feature that allows developers to create and manage client-side routes in their web applications.
- It provides a way to map URLs to views and view models.
84. What is a view model in Aurelia?
- A view model in Aurelia is a JavaScript class that is used to provide data and behavior for a view.
- It serves as the intermediary between the view and the model.
85. What is the syntax for defining a computed property in Aurelia?
| @computedFrom(‘property1’, ‘property2’) get computedProperty() { return … } |
86. What is the syntax for defining a custom element view in Aurelia?
| @customElement({ name: ‘custom-element’, template: ‘<template>…</template>’ }) |
87. What is the syntax for defining a custom attribute view in Aurelia?
| @customAttribute({ name: ‘custom-attribute’, template: ‘<template>…</template>’ }) |
88. How does Aurelia compare to other JavaScript frameworks?
Ans: Compared to other popular frameworks like Angular and React, Aurelia is known for its simplicity, flexibility, and ease of use. It has a clean and modular architecture, which makes it easier to scale and maintain large applications.
89. What is the Aurelia event aggregator?
- The Aurelia event aggregator is a powerful feature that allows developers to communicate between different parts of their application.
- It provides a way to publish and subscribe to events.
90. What is the Aurelia i18n plugin?
- The Aurelia i18n plugin is a plugin that provides internationalization support for Aurelia applications.
- It allows developers to create translations for their applications and provides a simple API for Aurelia applications.
91. What is the Aurelia store?
- The Aurelia store is a state management library for Aurelia applications.
- It provides a simple and intuitive API for managing application state.
92. What is the Aurelia dialog plugin?
- The Aurelia dialog plugin is a plugin that provides a way to display modal dialogs in Aurelia applications.
- It provides a simple and flexible API for creating and displaying dialogs.
93. What is the Aurelia animation plugin?
- The Aurelia animation plugin is a plugin that provides support for animations in Aurelia applications.
- It allows developers to create and animate elements in their applications using CSS or JavaScript.
94. What is the Aurelia CLI plugin?
- The Aurelia CLI plugin is a plugin that extends the functionality of the Aurelia CLI.
- It allows developers to add custom commands and functionality to the CLI.
95. What is the Aurelia UX framework?
- The Aurelia UX framework is a set of UI components and patterns that are designed to work seamlessly with Aurelia applications.
- It provides a set of customizable and extensible components, such as grids, forms, and dialogs.
96. What is the Aurelia webpack plugin?
- The Aurelia webpack plugin is a plugin that provides support for webpack in Aurelia applications.
- It allows developers to use webpack to build and bundle their applications, and provides a set of webpack loaders and plugins for working with Aurelia code.
| @bindable | @bind |
| @bindable is used to define a property on a custom element that can be bound to from the parent view, | @bind is used to specify the source property for a binding expression |
| @bindable is a decorator that can be used on class properties | @bind is an attribute that can be used in the view. |
97. What is the syntax for defining a custom element property observer in Aurelia?
| @computedFrom(‘propertyName’) get propertyNameChanged() { return … } |
98. List types of data bindings supported in Aurelia?
Ans: The types of data bindings supported in Aurelia are Overview, Bind, One-way, Two-way, One-time, String interpolation, Loops, Ref binding.
99. What is animator-velocity() in Aurelia?
Ans: animator-velocity(): It is the standard plugin of Aurelia. Here, you can use velocity animation library instead of CSS animations.
100. What is ui-virtualization() in Aurelia?
Ans: ui-virtualization(): This plugin is a useful library for handling large performance heavy UI tasks.
The Top 100 Aurelia Interview Questions and Answers cover a wide range of topics and are useful for both freshers and experienced developers to prepare for their interviews. You can follow us at freshersnow.com to expand your knowledge.