使用节点但在 JavaScript 中寻找绕过菱形继承的方法:
var util = require('util');
function Base(example_value) {
console.log(example_value);
this.example_property = example_value;
this.example_method = function() { ... };
}
function Foo(settings) {
var f = settings.f;
Base.call(x);
this.settings = settings;
}
util.inherits(Foo, Base);
function Bar(settings) {
var b = settings.b;
Base.call(b);
this.settings = settings;
}
util.inherits(Bar, Base);
var foo = new Foo({f: 'bar'});
// 'bar' gets printed and I can call methods from Base..
foo.example_method();
var bar = new Bar({b: 'foo'});
// 'foo' gets printed and I can call methods from Base..
bar.example_method();
这里没有问题..但是我需要在另一个包罗万象的对象中制作 Foo 和 Bar(和 Base)中可用的所有内容:
function Top(settings) {
Foo.call(this, settings);
Bar.call(this, settings);
}
util.inherits(Top, Foo);
util.inhertis(Top, Bar);
var top = new Top({some: 'value'});
'value' 被打印了两次,这不是我想要的。像这样进行继承可能不是最好的方法,因此寻找替代方案/建议来处理这种菱形结构。
附言没有包括原始代码,但进行了修改以希望简化 - 我已经手工完成了这个,不要认为有任何错误,但我试图传达的要点应该在那里。
最佳答案
你能使用委托(delegate)吗?
function Top(settings) {
this.foo = new Foo(settings);
this.bar = new Bar(settings);
}
Top.prototype.conflictingMethod = function() {
// use either this.foo or this.bar
}
Top.prototype.anotherMethod = function() {
return this.foo.anotherMethod();
}
你也可以使用 mixins,但你需要将它添加到你的类系统中。 Ext-JS 支持混合 http://www.sencha.com/learn/sencha-class-system
// My/sample/CanSing.js
Ext.define('My.sample.CanSing', {
sing: function(songName) {
alert("I'm singing " + songName);
}
});
// My/sample/CanPlayGuitar.js
Ext.define('My.sample.CanPlayGuitar', {
playGuitar: function() {
alert("I'm playing guitar");
}
});
// My/sample/CanComposeSongs.js
Ext.define('My.sample.CanComposeSongs', {
composeSongs: function() {
alert("I'm composing songs");
return this;
}
});
// My/sample/CoolGuy.js
Ext.define('My.sample.CoolGuy', {
extend: 'My.sample.Person',
mixins: {
canSing: 'My.sample.CanSing',
canPlayGuitar: 'My.sample.CanPlayGuitar'
}
});
// My/sample/Musician.js
Ext.define('My.sample.Musician', {
extend: 'My.sample.Person',
mixins: {
canSing: 'My.sample.CanSing',
canPlayGuitar: 'My.sample.CanPlayGuitar',
canComposeSongs: 'My.sample.CanComposeSongs'
}
});
// app.js
var nicolas = new My.sample.CoolGuy("Nicolas");
nicolas.sing("November Rain"); // alerts "I'm singing November Rain"
关于Javascript 菱形继承结构,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/16526830/