我有几个如何在方法中创建它们的属性

function MyClass() {
  this.myProperty = 'Value';
}

var obj = new MyClass();
console.log(obj.myProperty); // Output: Value

function MyClass() {
  var privateProperty = 'Private Value';

  this.getPrivateProperty = function() {
    return privateProperty;
  };

  this.setPrivateProperty = function(value) {
    privateProperty = value;
  };
}

var obj = new MyClass();
console.log(obj.getPrivateProperty()); // Output: Private Value
obj.setPrivateProperty('New Value');
console.log(obj.getPrivateProperty()); // Output: New Value

class MyClass {
  constructor() {
    this.myProperty = 'Value';
  }
}

var obj = new MyClass();
console.log(obj.myProperty); // Output: Value