UBB.Developers Forums Community Development Programming PHP and Server-side Scripting Substr

Well here's my problem. I have a variable that is equal to an absolute path. Then I need to take a substring of it, starting from the end until it reaches a /. For example, let's say I have a variable:


Basically, what I want to pull out is the "Public" part. But I don't know what the last part is in the program I have written... Any ideas?

Thanks.

[ February 12, 2001: Message edited by: PSX ]

Solution:
$Path =~ m!/([^/]+)$!gi;
my $value = $1;

Explained:
m!
Start a match, delimiter is !.

/
A slash

(
Start a group

[^/]
A single character that is not a forward slash

One or more of the previous single character
+


)
End group

$
End of string

!gi;
End regex. Make pattern searching global and case insensitive.

The value inside the first group is automagically stuck into $1 by Perl.

I'm not exactly understanding this. Could you possibly give me an actual example or can this be used in conjuction with substr? I'm a little confused...

Just add this:
$Path =~ m!/([^/]+)$!gi;

I gave you the code required above - BOTH lines, not just the first that MM quoted.

You can not do this just by using substr(), as it requires a static start position.

Well the position I want to start at is at the end of the path. Maybe I should re-explain my problem. I have a variable equal to a path. Like "/data1/va/UBB/Public" The last part of the path "Public" could be anything. So starting from the end I need to pull out anything until it hits a slash (/). So in that case I want it to pull out "Public". If the path was "/data1/va/UBB/Pub", then it would pull out "Pub". I'm sorry if this is the same thing I said, but what you are giving me, isn't exactly making the most sense to me... I think I understand what you have done, but not exactly how to apply it to what I am doing.

[ February 13, 2001: Message edited by: PSX ]

PSX - the method Charles gave you does what you want.

Charles - Why are you using the 'g' and 'i' modifiers here? (they seem unnecessary)

If you use a negative value for the offset, substr will start from the end.

From the PERL docs:

Yes, and if you don't know how long your path is, you CAN'T use substr.

Dave_L: Habit. *L*

Well... I finally figured out how to use the code you gave me. Thanks, Charles...