Angular Interview Questions 2024 — Access Specifiers in TypeScript and Angular

1. What Are the Different Access Specifiers in TypeScript?

Answer: TypeScript provides four main access specifiers:

• public: The default visibility. Members declared as public can be accessed from anywhere—inside the class, outside the class, or in child classes.
• private: Members marked as private are only accessible within the class they are defined in. This is useful for encapsulating and protecting the internal state.
• protected: protected members are accessible within the class and by derived classes. This is helpful when you want to allow child classes to use or override members, but still keep them hidden from other parts of the code.
• readonly: This modifier ensures that a property can only be set during initialization or in the constructor. It is often used for constants or configurations that should not change after being set.

2. How Do You Use Access Specifiers in an Angular Application?

Answer: In Angular, access specifiers are critical for managing the visibility and scope of properties and methods within components and services.

Example: Consider a component that handles form submissions. You might want to expose some properties to the template while keeping others private.