April 2018
Beginner
536 pages
13h 21m
English
In TypeScript, we can use interfaces to ensure that a class follows a particular specification:
interface LoggerInterface{
log(arg: any): void;
}
class Logger implements LoggerInterface {
log (arg: any){
if (typeof console.log === "function") {
console.log(arg);
} else {
console.log(arg);
}
}
}
In the preceding example, we have defined an interface LoggerInterface and a class Logger, which implements it. TypeScript will also allow you to use interfaces to declare the type of an object. This can help us to prevent many potential issues, especially when working with object literals:
interface UserInterface {
name: string;
password: string;
}
// Error property password is missing
let user: UserInterface = {
name: ""
};