javascript说JSON对象属性未定义，尽管不是 [英] javascript says JSON object property is undefined although it's not

问题描述

我有一个json对象，我将其打印到屏幕上(使用alert()函数):

I have a json-object, which I print to the screen (using alert()-function):

alert(object);

这是结果:

然后我要将id的值打印到屏幕上:

Then I want to print the value of the id to the screen:

    alert(object["id"]); 

结果是这样的:

如您所见，键"id"的值不是(!!!)未定义.

As you can see, the value of key "id" is not(!!!) undefined.

这到底是怎么回事?！

推荐答案

看起来您的json对象不是一个真正的对象，它是一个json字符串.为了将其用作对象，您将需要使用反序列化功能，例如JSON.parse(obj).对于如何反序列化JSON字符串，许多框架都有自己的实现.
当您尝试对真实对象执行alert(obj)时，结果将是[object Object]或类似的东西

Looks like your json object is not really an object, it's a json string. in order to use it as an object you will need to use a deserialization function like JSON.parse(obj). Many frameworks have their own implementation to how to deserialize a JSON string.
When you try to do alert(obj) with a real object the result would be [object Object] or something like that

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