Matching A value

[inforeqd]

Hopefully this is simple, but once again my expression matching is getting the best of me.

The setup is a java applet that uses POST to submit a
value to my cgi/perl script.

The submit is doing this when I run ethereal against it

sliderVal=-8.00 .. This is correct since I'm using a slider to have the user submit the value. However all I need is an expression statement to only get the -8.00 out of the POST.

I've tried things like this.. it all works up to the
my line

$chng=<STDIN>;
chomp $chng;
my($new_chng) = $chng =~ /(\d\d\d+)/;

But as you can see that isnt getting the -8.00 value, please note that the -8.00 is only an example. I have it setup to take from -8.00 to 8.00 in increments on .01.

Anyhelp would be great and once again ..thanks in advance
info

 

[mlibeson]

change /(\d\d\d+)/

to

/\=\s*([\+\-0-9\.]+)/

Michael Libeson

 

[rharsh]

Give this a try:

$chng =~ /sliderVal\s*=\s*(-?[\d\.]+)/;
my $new_chng = $1;

 

[inforeqd]

Michael

Thank you thank you .. that did just the trick.

Is there a site on the internet that better explains all these settings and how one could employ them. I know that this type of functionality is one of perls stronger points and the more and more I use perl the more I'm needed to do these things.

Also, while I have you .. I was wrong on my response. I need to send via the cgi script instead of -8.00 just an -800, so I need to chop out the decimal .. ideas on that?? What you posted worked exactly the way that I asked about. Again thanks.

thanks again
info

 

[PaulTEG]

remove the \. in michael's post

should be enough on the current.

perldoc perlre from your command line should give you a good start on regex (regular expressions)

hth
--paul


cigless ...

 

[mlibeson]

$chng=<STDIN>;
chomp $chng;
my($new_chng) = $chng;
$new_chng =~ s/^.*sliderVal\s*\=\s*([\+\-0-9]+)\.([0-9]+).*$/$1$2/;

$1 contains what is in the first set of parens and $2 has what is in the second set of paren.


Michael Libeson

 

[inforeqd]

Michael

Again, thanks! That did the trick.

info

 

[mlibeson]

Your welcome.

Michael Libeson

 

[chazoid]

Chapter 5 is a good intro to regular expressions... And appendix A for a quick reference:

http://learn.perl.org/library/beginning_perl/