Regex String Matching

Poblachtach32 has asked for the wisdom of the Perl Monks concerning the following question:

Hi,
I have a string which looks something like this -

begin=in+the+begining&str=Greed+Suffering&end=The+End+Part<br>
[download]

I want to match the part after str, up until the &.
in other words, I want to match Greed+Suffering
Heres my hack so far -


if($str =~ /str=[a-zA-Z]+/)
{
     print "\nMatch: $1";
}
[download]

I thought that $1 would have been assigned "Greed", but instead I get a runtime error saying that $1 is uninitailised. What am I doing wrong?

Comment on Regex String Matching Select or Download Code

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Re: Regex String Matching by sauoq (Abbot) on Sep 08, 2002 at 19:00 UTC
. . .I get a runtime error saying that $1 is uninitailised. You need to use parentheses to capture the match. `$str =~ /str=([a-zA-Z]+)/` Since you mention you want everything up to the next '&' you might be better off with a regex that does what you mean: `$str =~ /str=([^&])/` Edit:* Fixed that typo. Arien++ -sauoq "My two cents aren't worth a dime.";	[reply] [d/l] [select]
Re(2) Regex String Matching by Arien (Pilgrim) on Sep 09, 2002 at 04:55 UTC
`$str =~ /str=([^&])/;` There's a typo in that regex, you want the star inside the parens. (You are now putting the last non-ampersand following `str=`, if any, into `$1`.) `$str =~ /str=([^&])/;` — Arien	[reply] [d/l] [select]
Re: Regex String Matching by Steve_p (Priest) on Sep 08, 2002 at 19:01 UTC
I'm guessing that you are trying to parse parameters passed into a CGI script. If this is the case, you should not be using a Regex, but the CGI module instead and looking at the params passed in. I would suggest taking a look at Ovid's Web Programming With Perl course.	[reply]