how to make an interface in 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 class interface
interface IPerson {
name: string
age: number
hobby?: string[]
}
class Person implements IPerson {
name: string
age: number
hobby?: string[]
constructor(name: string, age: number, hobby: string[]) {
this.name = name
this.age = age
this.hobby = hobby
}
}
const output = new Person('john doe', 23, ['swimming', 'traveling', 'badminton'])
console.log(output)
Example 3: typescript class implements interface
interface Task{
name: String; //property
run(arg: any):void; //method
}
class MyTask implements Task{
name: String;
constructor(name: String) {
this.name = name;
}
run(arg: any): void {
console.log(`running: ${this.name}, arg: ${arg}`);
}
}
let myTask: Task = new MyTask('someTask');
myTask.run("test");
Example 4: typescript interface
interface NumberOrStringDictionary {
[index: string]: number | string;
length: number; // ok, length is a number
name: string; // ok, name is a string
}Try
Example 5: ts extends
class Animal {
name: string;
constructor(theName: string) { this.name = theName; }
move(distanceInMeters: number = 0) {
console.log(`${this.name} moved ${distanceInMeters}m.`);
}
}
class Snake extends Animal {
constructor(name: string) { super(name); }
move(distanceInMeters = 5) {
console.log("Slithering...");
super.move(distanceInMeters);
}
}
class Horse extends Animal {
constructor(name: string) { super(name); }
move(distanceInMeters = 45) {
console.log("Galloping...");
super.move(distanceInMeters);
}
}
let sam = new Snake("Sammy the Python");
let tom: Animal = new Horse("Tommy the Palomino");
sam.move();
tom.move(34);