What's the fastest way to iterate over an object's properties in Javascript?

Question

I know that I can iterate over an object\'s properties like this:

for (property in object)
{
    // do stuff
}

I also know that the fastest

Answer 1

If you don't know the names of the properties, for..in is a good way to enumerate them. If you do, you're better off with explicit dereference.

Answer 2

An object's properties are unordered by definition. The lack of order means that there is no "forwards", and therefore there is no "backwards" either.