Static methods and properties are defined on the class/constructor itself, not on instance objects. These are specified in a class definition by using the static keyword.
class MyClass {
static myStaticMethod() {
return 'Hello';
}
static get myStaticProperty() {
return 'Goodbye';
}
}
console.log(MyClass.myStaticMethod()); // logs: "Hello"
console.log(MyClass.myStaticProperty); // logs: "Goodbye"
We can see that static properties are not defined on object instances:
const myClassInstance = new MyClass();
console.log(myClassInstance.myStaticProperty); // logs: undefined
However, they are defined on subclasses:
class MySubClass extends MyClass {};
console.log(MySubClass.myStaticMethod()); // logs: "Hello"
console.log(MySubClass.myStaticProperty); // logs: "Goodbye"