Impelsys Senior Angular Developer Interview Questions and Answers

ES6 features are modern JavaScript enhancements that improve code readability and efficiency.

• Arrow functions for concise syntax: const add = (a, b) => a + b;

• Let and const for block-scoped variables: let x = 5; const y = 10;

• Template literals for string interpolation: const name = 'John'; console.log(`Hello, ${name}!`);

• Destructuring assignment for easily extracting values from arrays or objects: const { firstName, las...read more

Shallow copy only copies the references of nested objects, while deep copy creates new copies of nested objects.

• Shallow copy creates a new object but does not create copies of nested objects.

• Deep copy creates a new object and also creates copies of nested objects.

• Shallow copy is faster and more memory efficient, but changes to nested objects affect both original and copied objects.

• Deep copy is slower and consumes more ...read more

Arrow functions are concise and do not bind their own 'this' value, while regular functions have their own 'this' value and can be used as constructors.

• Arrow functions have a more concise syntax compared to regular functions.

• Arrow functions do not have their own 'this' value, they inherit it from the parent scope.

• Regular functions have their own 'this' value, which can be useful for object-oriented programming and cons...read more

Subject vs BehaviourSubject in Angular

• Subject is a basic observable that emits values to subscribers

• BehaviourSubject is a type of Subject that stores the latest value and emits it to new subscribers

• BehaviourSubject requires an initial value when created

Custom pipes in Angular are used to transform data in templates.

• Custom pipes are created using the @Pipe decorator in Angular.

• To use a custom pipe in HTML, you need to include it in the declarations array of the NgModule.

• You can pass parameters to custom pipes in HTML using the pipe symbol (|).

• Example: {{ value | customPipe:param1:param2 }}

ng-template, ng-content, and ng-container are Angular structural directives used for template rendering and content projection.

• ng-template is used to define a template that can be rendered conditionally or multiple times.

• ng-content is used for content projection, allowing the insertion of content from a parent component into a child component.

• ng-container is a grouping element that doesn't interfere with styles or layo...read more

ForkJoin is an operator in Angular that allows for parallel execution of multiple observables.

• ForkJoin combines the values from multiple observables and emits them as an array when all observables complete.

• It waits for all observables to complete and then emits the combined result.

• Example: forkJoin([observable1, observable2]).subscribe(result => console.log(result));

Wildcard routes in Angular allow for handling unknown routes and redirecting to a default route.

• Wildcard route is denoted by '**' in the route configuration.

• It is typically used at the end of the route configuration to handle unknown routes.

• Example: { path: '**', redirectTo: '/404' }

Handle errors in fetching API calls by implementing error handling mechanisms.

• Use try-catch blocks to catch errors during API calls

• Implement error handling logic in the catch block to handle different types of errors

• Display user-friendly error messages to inform users about the issue

• Use HTTP status codes to identify the type of error (e.g. 404 for not found)

• Implement retry mechanisms for temporary network issues

I have extensive experience in Angular development, strong problem-solving skills, and a proven track record of delivering high-quality projects on time.

• I have X years of experience working with Angular framework

• I have successfully completed projects A, B, and C using Angular

• I am proficient in problem-solving and troubleshooting issues in Angular applications