Question

I’m trying to use a hardcoded 64bit integer in a string variable.

Simplfied I want to do something like this:

$i = 76561197961384956;
$s = "i = $i";

Which should result in s being:

i = 76561197961384956

This does obviously not work as PHP cast big integers to float, therefore s is:

i = 7.65611979614E+16

While several other methods like casting etc. fail, I found number_format() and use it like this:

$s = "i = " . number_format($i, 0, '.', '');

But this results in s being:

i = 76561197961384960

Looks like an approximation problem, but how to fix this?

Answer 1

You’re losing the precision on the assignment, not on the string conversion. If this variable’s value is actually hardcoded, and you can’t change that, there’s nothing you can do.

A line like:

$i = 76561197961384956;

will always lose precision. If you need to keep the whole thing, store it into a string, you can’t store it as an int like that and keep all the digits.