Top Typescript QuestionsIn this post we will look at Typescript Interview questions. Examples are provided with explanation.
What is Typescript?
What are the advantages of using Typescript?
- Code scalability with "Interface oriented development"
- TypeScript helps you dealing with teams.For example, Microsoft made an awesome community effort work.
- Refactoring by typescript tools are faster and easier.
- Types have a proven ability to enhance code quality and understandability.
- Types increase your agility when doing refactoring. It is better for the compiler to catch errors than to have things fail at runtime.
- Types are one of the best forms of documentation you can have. The function signature is a theorem and the function body is the proof.
What can we convert string to number using Typescript?In Typescript this can be achieved in 4 ways
Using Unary like +,* operator
var a = "31"; var b: number = +a;
new testClass(args);ngOnInit is a life cycle hook called by Angular to indicate that Angular is done creating the component.
What is Decision Making in Typescript?Decision-making structures required so that the programmer specifies one or more conditions to be evaluated or tested by the program, along with a statement or statements to be executed if the condition is determined to be true, and optionally, other statements to be executed if the condition is determined to be false.
A decision-making construct evaluates a condition before the instructions are executed.
What is Basic Syntax in Typescript?Syntax defines a set of rules for writing programs. Every language specification defines its own syntax.
Your First TypeScript Code
Let us start with the traditional "People" example â var message:string = "People" console.log(message)
For eg. Visual Studio or Chrome's dev tools)
What are different components of TypeScript?
- Language â The most important part for developers is the new language. The language consist of new syntax, keywords and allows you to write TypeScript.
- Language Service â TypeScript language service which powers the interactive TypeScript experience in Visual Studio, VS Code, Sublime, the TypeScript playground and other editor.
What are Ambients in TypeScript?
- Ambient declarations are a way of telling the TypeScript compiler that the actual source code exists elsewhere.
- When you are consuming a bunch of third party js libraries like jquery/angularjs/nodejs you canât rewrite it in TypeScript. Ensuring typesafety and intellisense while using these libraries will be challenging for a TypeScript programmer. Ambient declarations help to seamlessly integrate other js libraries into TypeScript.