typescript abstract class declaring subclass function code example

Example 1: abstract classes in typescript

abstract class Department {
  constructor(public name: string) {}

  printName(): void {
    console.log("Department name: " + this.name);
  }

  abstract printMeeting(): void; // must be implemented in derived classes
}

class AccountingDepartment extends Department {
  constructor() {
    super("Accounting and Auditing"); // constructors in derived classes must call super()
  }

  printMeeting(): void {
    console.log("The Accounting Department meets each Monday at 10am.");
  }

  generateReports(): void {
    console.log("Generating accounting reports...");
  }
}

let department: Department; // ok to create a reference to an abstract type
department = new Department(); // error: cannot create an instance of an abstract class
Cannot create an instance of an abstract class.2511Cannot create an instance of an abstract class.department = new AccountingDepartment(); // ok to create and assign a non-abstract subclass
department.printName();
department.printMeeting();
department.generateReports();
Property 'generateReports' does not exist on type 'Department'.2339Property 'generateReports' does not exist on type 'Department'.Try

Example 2: abstract classes in typescript

abstract class Animal {
  abstract makeSound(): void;

  move(): void {
    console.log("roaming the earth...");
  }
}Try