PHP对象到JSON格式[重复]

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PHP json_encode class private members 8 answers
PHP json_encode类私有成员8个答案

Consider this stripdown class:

考虑这个条带类：

class foo {

    private $fooVar;


    public getFooVar(){

    }

}


$fooObj = new foo();

want i want/need to do is convert this to JSON format so I thought of putting

我希望/需要做的是将其转换为JSON格式，所以我想放

echo json_encode($fooObj);

however it doesnt work, i don't have fooVar and im guessing because $fooVar is private..

但它不起作用，我没有fooVar和我猜测因为$ fooVar是私人..

any other way I can do this without having to compromise and make $fooVar public?

我可以做任何其他方式，而不必妥协并公开$ fooVar？

Thanks a bunch!

谢谢你！

3 个解决方案

#1

If you're using PHP 5.3 (or earlier), you can't really do what you're asking for easily. You won't get the methods encoded in JSON because JSON is a data format and doesn't include functions, and you won't get the property because it's a private property. You know this much already, but it's worth re-iterating to point out that you're right, it's not easy. Even writing the getter as a magic __get() method to turn it into a read-only public property won't work in this case.

如果您使用的是PHP 5.3（或更早版本），则无法轻松完成您的要求。您将不会获得以JSON编码的方法，因为JSON是一种数据格式，并且不包含函数，并且您不会获取该属性，因为它是私有属性。你已经知道了这一点，但值得重新指出你是对的，这并不容易。即使将getter作为一个神奇的__get（）方法将其转换为只读公共属性，也不会在这种情况下起作用。

In PHP 5.3, there are a couple of work arounds you could use.

在PHP 5.3中，您可以使用几种解决方法。

Reflection. PHP includes a Reflection API, which allows you to access details about objects and classes, including reading values from private members. Obviously, however, this would mean writing a fair bit of code to get at the value, and it won't be fast either.

反射。 PHP包含一个Reflection API，它允许您访问有关对象和类的详细信息，包括从私有成员读取值。然而，显然，这意味着要编写一些代码以获得该值，并且它也不会很快。
Write the json_encode call inside the class. That way you can include private properties. I would suggest using get_object_vars($this) inside the object to get at the private properties in a JSON friendly way.

在类中写入json_encode调用。这样你就可以包括私人财产。我建议在对象中使用get_object_vars（$ this）以JSON友好的方式获取私有属性。

If you're using PHP 5.4, you have an additional option:

如果您使用的是PHP 5.4，则还有一个选项：

PHP 5.4 introduces a JsonSerializable interface. Add implements JsonSerializable to your class, and write a method called jsonSerialize(). This method should return the data that you want to be in the JSON string. You can include or exclude whichever public or private properties you want.
PHP 5.4引入了JsonSerializable接口。将实现JsonSerializable添加到您的类，并编写一个名为jsonSerialize（）的方法。此方法应返回您要在JSON字符串中的数据。您可以包含或排除您想要的任何公共或私人财产。

PHP 5.5 hasn't been released yet, but it will add another option for you:

PHP 5.5尚未发布，但它将为您添加另一个选项：

PHP 5.5 will introduce a more complex syntax for defining properties, which will allow you to define properties as public but read-only, or to include more complex logic for them in the getter and setter, but still have them as properties. It will work much like the __get() and __set() methods do now, but with the variables explicitly defined as properties, which will mean that they should be accessible to the JSON serialiser, whereas currently with __get() they're not.
[EDIT] - note, the above paragraph is incorrect; the feature described did not make it into the PHP 5.5 release. Too early yet to say yet whether it'll get into 5.6 or not.
PHP 5.5将引入更复杂的语法来定义属性，这将允许您将属性定义为公共但只读，或者在getter和setter中包含更复杂的逻辑，但仍将它们作为属性。它的工作方式与现在的__get（）和__set（）方法非常相似，但是变量显式定义为属性，这意味着它们应该可以被JSON序列化程序访问，而目前使用__get（）则不行。 [编辑] - 注意，上段不正确;所描述的功能没有进入PHP 5.5版本。太早还没有说它是否会进入5.6。

Hope that helps.

希望有所帮助。

#2

JSON decoding is a bit tricky with custom types, since you do not have information about type in JSON. All you have is generic objects (hash tables) and arrays.

JSON解码对于自定义类型有点棘手，因为您没有关于JSON类型的信息。你所拥有的只是通用对象（哈希表）和数组。

But to serialize objects to JSON, you can implement JsonSerializable interface. Then json_encode function will do what you want.

但是要将对象序列化为JSON，您可以实现JsonSerializable接口。然后json_encode函数将执行您想要的操作。

#3

This would print a JSON with all of the properties (public, private and protected) of class foo:

这将打印一个包含类foo的所有属性（public，private和protected）的JSON：

$reflection = new ReflectionClass('foo');
$properties = $reflection->getdefaultProperties();

echo json_encode($properties);

#1