There are times that you will need to get the size of an object but the lack of .length maybe will drive you crazy. The solution is simple. Just create a function in which you pass the object as a parameter and then loop through the object keys. With the help of .hasOwnProperty(key) you can increase the value of a counter variable. After the loop you simply return this variable. Have a look at the code below. I find it quite a useful snippet.

Object.size = function (obj) {
	var size = 0, key;
	for (key in obj) {
		if (obj.hasOwnProperty(key)) size++;
	}
	return size;
};