PHP best way to MD5 multi-dimensional array?

Question

What is the best way to generate an MD5 (or any other hash) of a multi-dimensional array?

I could easily write a loop which would traverse through each level of the

Answer 1

Note that serialize and json_encode act differently when it comes to numeric arrays where the keys don't start at 0, or associative arrays. json_encode will store such arrays as an Object, so json_decode returns an Object, where unserialize will return an array with exact the same keys.