Question

How to store private data via class constructor in JavaScript ES6

Answer 1

class CTest {
    constructor(counter, callback_f) {
        Object.assign(this, {
            dec() {
                if (counter > 4) return;
                counter++;
                console.log(counter);
                if (counter === 4) {
                    callback_f();
                }
            }
        });
    }
}

const obj = new CTest(0, () => console.log('END'));

obj.dec();
obj.dec();
obj.dec();
obj.dec();


 
/*
run:
      
1
2
3
4
END
 
*/

 

70+ SQL courses for beginners and professionals