How to list the properties of a JavaScript object?

Question

Say I create an object thus:

var myObject =
        {\"ircEvent\": \"PRIVMSG\", \"method\": \"newURI\", \"regex\": \"^http://.*\"};

What is

Answer 1

In modern browsers (IE9+, FF4+, Chrome5+, Opera12+, Safari5+) you can use the built in Object.keys method:

var keys = Object.keys(myObject);

The above has a full polyfill but a simplified version is:

var getKeys = function(obj){
   var keys = [];
   for(var key in obj){
      keys.push(key);
   }
   return keys;
}

Alternatively replace var getKeys with Object.prototype.keys to allow you to call .keys() on any object. Extending the prototype has some side effects and I wouldn't recommend doing it.