确定Javascript对象是否是“复杂”对象。对象或只是一个字符串 [英] Determining if a Javascript object is a "complex" object or just a string

问题描述

我希望能够传递字符串文字，

I want to be able to pass either a string literal,

'this is a string'

或javascript对象，

or a javascript object,

{one: 'this', two: 'is', three: 'a', four: 'string' }

作为函数的参数，并根据它是字符串还是对象采取不同的操作。我如何确定哪个是真的？

as argument to a function, and take different actions depending on whether it's a string or an object. How do I determine which is true?

具体来说，我想迭代对象的属性，如果属性是字符串，则进行一些解析，但是如果属性是对象，则递归嵌套。我已经想出如何使用 $。each（）来迭代对象的属性，但是如果我只是对字符串执行此操作，它会将字符串视为一系列字母而不是一个单一的东西。我可以通过其他方式解决这个问题吗？

To be specific, I want to iterate over the properties of an object, and do some parsing if a property is a string, but nest recursively if the property is an object. I've figured out how to use $.each() to iterate over the properties of the object, but if I just do this with the string, it treates the string as an array of letters rather than as a single thing. Can I get around this some other way?

推荐答案

var data = {
    foo: "I'm a string literal",
    bar:  {
       content: "I'm within an object"
    }        
};

jQuery

$.each(data, function(i, element){
    if($.isPlainObject(element){
       // we got an object here
    }
});

有类似的方法，如 jQuery lib中的$ .isArray（）或 $。isFunction（）。

原生Javascript

for(var element in data){
   if(toString.call(element) === '[object Object]'){
      // we got an object here
   }
}

使用 hack'ish 方式与 toString 有一个好处，你可以确定它是真的一个对象和一个数组。两者，对象和数组都会使用 typeof元素返回 object 。

To use the hack'ish way with toString has the advantage, that you can identify whether it is really an object and an array. Both, objects and arrays would return object by using typeof element.

长篇故事简而言之，您不能依赖 typeof 运算符来区分真正的对象和数组。为此，您需要 toString.call（）。如果您只是需要知道它是否是任何对象， typeof 就可以了。

Long story short, you cannot rely on the typeof operator to distinguish true objects and arrays. For that you need the toString.call(). If you just need to know whether it is any object or not, typeof is just fine.

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