Interfaces
What are interfaces? There are no “interfaces” in JavaScript. That is correct. Interfaces a TypeScript-specific concept that exists only in the TypeScript project. We can prove this by creating an interface within the TypeScript playground; it will not compile to JavaScript.
Interfaces are essentially objects with their properties annotated. Once an interface is created, that object becomes a data type that you can check against.
Let’s look at a traditional JavaScript object and a TypeScript interface.
index.js
constperson={name:'',nickName:'',location:'',age:0,}
index.ts
interfacePerson{name:string;nickName:string;location:string;age:number;}
We can now assign a const with the type of Person and provide values.
constperson:Person={name:'Peter Parker',nickName:'Spider-Man',location:'New York, NY',age:27}console.log(person);
If you...