TypeScript Interview Questions and Answers
The word of development is rapidly growing, so as the programming languages associated with it. TypeScript is one of these increasingly popular programming languages. We will discuss several advanced TypeScript interview questions while further continuing here for your practice. TypeScript is an object-oriented, open-source, strongly typed and compiled programming language. It’s a typed superset of JavaScript (compiled to JavaScript) and can be used for JavaScript application development supported to server-side and client-side execution.
Simplifying it, TypeScript is an advanced version of JavaScript with additional features to help both programming language and new tool requirements for developers. With the conclusion of basic TypeScript knowledge, now let’s continue with our expert-selected, crucial TypeScript interview questions with the suggested answer that may help you crack your next big interview.
Benefits of TypeScript
- With TypeScript, the production of pure object-oriented code is possible even with limited knowledge as this is completely object-oriented programming.
- It can be used for both server-side and client-side development alike.
- TypeScript comes with types that make code easier to read and void major errors.
- As it’s a package, TypeScript can be installed on projects via npm. This will make new features available and compile to all modern browsers.
- TypeScript offers an API for DOM manipulation.
- It also has the concept of the namespace by Module defining.
- With IDE support here, developers will save a ton of valuable time here.
Most Frequently Asked TypeScript Interview Questions
A module in TypeScript is a file containing functions, classes, or values. Users can make them public (to be visible from other modules) just by exporting them. Non exported modules stay private to other modules. These TypeScript interview questions are extremely career-promoting for both freshers as well as experienced professionals when practiced properly.
The export keyword is used to export any declaration such as function, variables, interface, or type alias. The export * from "module" can be used by a module to wrap one or more modules and combine together their exporting. Whereas, the import keyword is used to export declaration.
The Arrow function in TypeScript is used to eliminate the repetitive typing of function. It also lexically captures the meaning of both this and arguments.
In TypeScript, Getter is the method to obtain the value of a specific property, whereas the setter method is used to set the value of the specific property.
Developers can use the optional parameter to declare parameters in function optional so that the requirement to pass the value to optional parameters gets eliminated. We have to use “?” at the end of a parameter to mark it optional as just shown below.
function functionName(par1: number, par2?: number) {
}
Here par2 is an optional parameter.
TypeScript uses the keyword ‘extends’ to support inheritance. The syntax will be as following:
class child_class_name extends parent_class_name