define methods in interface typescript code example

Example 1: typescript interface function

interface IEmployee {
    empCode: number;
    empName: string;
    getSalary: (number) => number; // arrow function
    getManagerName(number): string; 
}

Example 2: typescript extend interface

//declare interface to be extended
interface Vehicle {
  brand: string;
  plateNumber: number;
}

interface Car extends Vehicle {}