Javascript从孩子访问父母

时间:2014-01-07 09:06:19

标签: javascript oop parent-child

我正在尝试找出一种子类访问父类的方法,当父类永远不知道它有哪些子类时?

我正在使用Object.create来创建我的类,现在我正在这样做。请注意子类“obj.parent = parentClass”

必须有更好的方法来做到这一点,但我不知道。

var parentClass = (function() {
    var obj = Object.create({});

    var _parentProperty = 'foo';

    Object.defineProperties(obj,
        {
            'parentProperty': {
                configurable: false,
                enumerable: true,
                set: function(value) {
                    _parentProperty = value;
                },
                get: function() {
                    return _parentProperty;
                }
            },
            'parentMethod': {
                value: function() {
                    alert('Parent method called');
                },
                writable: false,
                configurable: false,
                enumerable: false
            }
        }
    );

    return obj;
})();

var childClass = (function() {
    var obj = Object.create(parentClass);
    obj.parent = parentClass;

    var _childProperty = 'bar';

    Object.defineProperties(obj,
        {
            'childProperty': {
                configurable: false,
                enumerable: true,
                set: function(value) {
                    _childProperty = value;
                },
                get: function() {
                    return _childProperty;
                }
            },
            'childMethod': {
                value: function() {
                    alert('Child method called');
                },
                writable: false,
                configurable: false,
                enumerable: false
            },
            'callParent': {
                value: function() {
                    alert(this.parent.parentProperty);
                    this.parent.parentMethod();
                },
                writable: false,
                configurable: false,
                enumerable: false
            }
        }
    );

    return obj;
});

var myClass = new childClass();
myClass.callParent();

1 个答案:

答案 0 :(得分:1)

在两个parentClass&的两个Object.defineProperties对象构造函数中使用return关键字。儿童班

<script>
var parentClass = (function() {
    var obj = Object.create({});

    var _parentProperty = 'foo';

    return Object.defineProperties(obj,
        {
            'parentProperty': {
                configurable: false,
                enumerable: true,
                set: function(value) {
                    _parentProperty = value;
                },
                get: function() {
                    return _parentProperty;
                }
            },
            'parentMethod': {
                value: function() {
                    alert('Parent method called');
                },
                writable: false,
                configurable: false,
                enumerable: false
            }
        }
    );
})();


var childClass = (function() {
    var obj = Object.create(parentClass);
    obj.parent = parentClass

    var _childProperty = 'bar';

    return Object.defineProperties(obj,
        {
            'childProperty': {
                configurable: false,
                enumerable: true,
                set: function(value) {
                    _childProperty = value;
                },
                get: function() {
                    return _childProperty;
                }
            },
            'childMethod': {
                value: function() {
                    alert('Child method called');
                },
                writable: false,
                configurable: false,
                enumerable: false
            },
            'callParent': {
                value: function() {
                    alert(this.parent.parentProperty);
                    this.parent.parentMethod();
                },
                writable: false,
                configurable: false,
                enumerable: false
            }
        }
    );
});

var myClass = new childClass();
myClass.callParent();
</script>