Get value of first object property

Question

I have a simple object that always has one key:value like var obj = {'mykey':'myvalue'}

What is the fastest way and elegant way to get the value without really doing this?

for (key in obj) {
  console.log(obj[key]);
  var value = obj[key];
}

Like can I access the value via index 0 or something?

Solution 1

var value = obj[Object.keys(obj)[0]];

Object.keys is included in javascript 1.8.5. Please check the compatibility here http://kangax.github.io/es5-compat-table/#Object.keys

Edit:

This is also defined in javascript 1.8.5 only.

var value = obj[Object.getOwnPropertyNames(obj)[0]];

Reference:

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_Objects?redirectlocale=en-US&redirectslug=JavaScript%2FGuide%2FWorking_with_Objects#Enumerating_all_properties_of_an_object

Solution 2

function firstProp(obj) {
    for(var key in obj)
        return obj[key]
}

Comments

[Felix Kling]

Please note that the problem has nothing to do with JSON at all. It seems you are confusing JavaScript object literals (constructs of the JavaScript language syntax) with JSON (a language-independent data-exchange format, like XML or CSV). I will edit your question accordingly. See also: There is no such thing as a "JSON object".

[Felix Kling]

related: JavaScript: Get first and only property name of object