example.ts

// Parent interface
interface IParent {
    name: string;
    value: number;
    getInfo(): string;
}

// Child interface extending the parent
interface IChild extends IParent {
    childSpecificMethod(): void;
}

// Parent class
class Parent implements IParent {
    private _name: string;
    private _value: number;

    constructor(name: string, value: number) {
        this._name = name;
        this._value = value;
    }

    get name(): string {
        return this._name;
    }

    set name(newName: string) {
        this._name = newName;
    }

    get value(): number {
        return this._value;
    }

    set value(newValue: number) {
        this._value = newValue;
    }

    getInfo(): string {
        return `Name: ${this._name}, Value: ${this._value}`;
    }

    // Method to change multiple parameters at once
    updateInfo(name?: string, value?: number): void {
        if (name !== undefined) this._name = name;
        if (value !== undefined) this._value = value;
    }
}

// Child class
class Child extends Parent implements IChild {
    private _childProperty: string;

    constructor(name: string, value: number, childProperty: string) {
        super(name, value);
        this._childProperty = childProperty;
    }

    get childProperty(): string {
        return this._childProperty;
    }

    set childProperty(newProperty: string) {
        this._childProperty = newProperty;
    }

    childSpecificMethod(): void {
        console.log("This is a child-specific method");
    }

    // Override parent method
    getInfo(): string {
        return `${super.getInfo()}, Child Property: ${this._childProperty}`;
    }
}

// Usage example
const parent = new Parent("ParentName", 100);
console.log(parent.getInfo());  // Output: Name: ParentName, Value: 100

parent.updateInfo("NewParentName", 200);
console.log(parent.getInfo());  // Output: Name: NewParentName, Value: 200

const child = new Child("ChildName", 50, "ChildProp");
console.log(child.getInfo());  // Output: Name: ChildName, Value: 50, Child Property: ChildProp

child.name = "NewChildName";
child.value = 75;
child.childProperty = "NewChildProp";
console.log(child.getInfo());  // Output: Name: NewChildName, Value: 75, Child Property: NewChildProp

child.childSpecificMethod();  // Output: This is a child-specific method