你如何在PHP中使用md5（）的raw_output返回值？

Question

I'm pretty inexperienced in PHP so this may be obvious to some of you, but if I call md5($mystring,true) in PHP it says it returns a "raw binary format with a length of 16". So what is that? Is it an array? An array of what? How do I read the individual bits and bytes of that return value?

None of the examples I can find online use it without going straight into base64_encode() or something. I just want to be able to check the fifth bit, or the third byte, for example.

Answer 1

It returns it as a "string" with each Character being a byte of the output. What you might consider instead is using the hex output of md5() without the second parameter and converting substrings of it to numbers using intval() with 16 as the base parameter. Like so:

$hash = md5($raw);
$byte = intval(substr($hash, 0, 2), 16);