PHP get rid of slashes full path

Question

Hey everyone,

I have a full path which I would like to remove certain levels of it. So for instance,

/home/john/smith/web/test/testing/nothing/

I would like to get rid of 4 levels, so I get

/test/testing/nothing/

What would be a good of doing this?

Thanks

Answer 1

A simple solution is to slice the path up into parts, and then manipulate the array before sticking it back together again:

join("/", array_slice(explode("/", $path), 5));

Of course, if you wanted to remove that specific path, you could also use a regular expression:

preg_replace('~^/home/john/smith/web/~', '', $path);

One word of advice though. If your application is juggling around with paths a lot, it may be a good idea to create a class to represent paths, so as to encapsulate the logic, rather than have a lot of string manipulations all over the place. This is especially a good idea, if you mix absolute and relative paths.

Answer 2

Why are you all using regular expressions for something that requires absolutely no matching; CPU cycles are valuable!

str_replace would be more efficient:

$s_path = '/home/john/smith/web/test/testing/nothing/';
$s_path = str_replace('john/smith/web/test/', '', $s_path);

And use realpath() to resolve any '../../' paths.

And remember dirname(__FILE__) gets the CWD and rtrim() is extremely useful for removing trailing slashes..