Dependency Injection using constructor

 // Service class that requires a dependency

class Service {

constructor(dependency) {

this.dependency = dependency;

}

doSomething() {

this.dependency.doAction();

}

}

// Dependency class

class Dependency {

doAction() {

console.log("Dependency is performing an action.");

}

}

// Creating instances and injecting dependencies

const dependency = new Dependency();

const service = new Service(dependency);

service.doSomething();