AngularJS：设置属性，同时保持绑定：有没有更好的办法？ [英] AngularJS: Setting properties while keeping a binding: is there a better way?

问题描述

如果我有一个服务的一些属性，我想设置为我从一个网络调用回数据，我可以做这样的事情：

If I have some property in a service that I want to set equal to the data I get back from a network call, I can do something like this:

//SERVICE//
thisService.property = data;
//SERVICE//

在我的控制，我可以做的：

and in my controller I can do:

//CONTROLLER//
this.property = ThisService.property;
//CONTROLLER//

这样我可以绑定到它的HTML和有它动态更新：

so that I can bind to it in the HTML and have it dynamically update:

//VIEW//
{{property}}
//VIEW//

然而，正如你可能知道，这是行不通的。该controller.property仍然是不确定的，因为这行：

However, as you may know, this does not work. The controller.property remains undefined, as this line:

thisService.property = data;

将创建thisService.property一个新的参考，而旧人，在控制器中设置，将不指向新的数据。

will create a new reference for thisService.property, and the old one, set in the controller, will not point to the new data.

所以，我要做的就是在包装另一个对象的数据，做这样的事情：

So, what I have to do is wrap the data in another object, and do something like this:

//SERVICE//
thisService.property = {};
thisService.property.property = data;
//SERVICE//

//CONTROLLER//
this.property = ThisService.property;
//CONTROLLER

//VIEW//
{{property.property}}
//VIEW//

这是相当粗糙和丑陋。是否有实现这一目标的一个更好，更清洁的方式？

This is rather crude and ugly. Is there a better, cleaner way of achieving this?

推荐答案

创建一个getter。

Create a getter.

Object.defineProperty(this, 'property',
                      { get: function() { return ThisService.property; }});

现在控制器的属性总是引用当前服务的属性。

Now the controller's property will always refer to the current service's property.

如果该服务的值设置只有一次，不会再发生变化，那么我建议你使用一个承诺，虽然。这将告诉更多关于发生了什么。

If the service's value is set only once and never changes again, then I'd recommend using a promise though. That would tell more about what's going on.

Plunker

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