Perl Guru Forums: Perl Programming Help: Regular Expressions: Validate string

CGI/Perl Guide | Learning Center | Forums | Advertise | Login

Site Search: in


	MAIN INDEX	SEARCH POSTS	WHO'S ONLINE	LOG IN

Home: Perl Programming Help: Regular Expressions:
Validate string

mhassan
Novice

Jan 21, 2010, 9:31 AM

Post #1 of 3 (1710 views)

Validate string	Can't Post

Hi,
I want to check if the $mystring variable is less than or equal to 3 characters using regex. If variable string is less than or equal to 3 then print "your string is less than or equal to 3 characters". Below is my test code.

Code

#!/usr/bin/perl -w 
 
use strict; 
 
my $mystring = "lsdkajsssssssssssssssssssssfkljadskljfkldsaj"; 
my $regex = ".{0,3}"; 
 
if ($mystring =~ m/.{0,3}/){ 
	 
	print "your string is less than or equal to 3 characters\n"; 
} 
 
exit;

This code prints "your string is less than or equal to 3 characters" even though i don't want the it to since $mystring is larger than 3 characters. I don't know anything about regex. Any help?

toolic
User

Jan 21, 2010, 9:51 AM

Post #2 of 3 (1704 views)

Re: [mhassan] Validate string [In reply to]	Can't Post

If you really think you need to use a regex, then you should anchor the pattern:

Code

if ($mystring =~ m/^.{0,3}$/){

However, using the built-in length function seems more appropriate than a regex for this task:

Code

if (length($mystring) <= 3) {

mhassan
Novice

Jan 21, 2010, 10:57 AM

Post #3 of 3 (1703 views)

Re: [toolic] Validate string [In reply to]	Can't Post

Thanks a lot it works!. I needed to use regex to check length since $mystring and $regex is one of the element of an array. The above code was just a test code..

Search for (options)

Web Applications & Managed Hosting Powered by Gossamer Threads
Visit our Mailing List Archives