Perl Guru Forums: Perl Programming Help: Beginner: need help removing charactors from 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: Beginner:
need help removing charactors from string

gerble1000
User

Jun 9, 2012, 6:44 AM

Post #1 of 14 (2673 views)

need help removing charactors from string	Can't Post

how to remove every character from a string except these assci codes
48 to 57
63 to 90
97 to 122
32
39 to 41
44 to 46
127
8

how would i go about removing all other charactors from the string any ideas would be great :)

FishMonger
Veteran / Moderator

Jun 9, 2012, 8:29 AM

Post #2 of 14 (2672 views)

Re: [gerble1000] need help removing charactors from string [In reply to]	Can't Post

What have you tried?

The most common approach would be to use a regex with a negated character class.

gerble1000
User

Jun 9, 2012, 8:53 AM

Post #3 of 14 (2669 views)

Re: [FishMonger] need help removing charactors from string [In reply to]	Can't Post

i tried this

my $message = "Hello frank it's me graham ring me when u get 2 mins :)...";

$message =~ s/[^a-zA-Z0-9]*//g;
but this does not allow me to have commas and spaces and more.
i want to allow curtain charactors through

FishMonger
Veteran / Moderator

Jun 9, 2012, 9:04 AM

Post #4 of 14 (2668 views)

Re: [gerble1000] need help removing charactors from string [In reply to]	Can't Post

Have you tried expanding the character class to include all of the desired characters?

gerble1000
User

Jun 9, 2012, 9:34 AM

Post #5 of 14 (2665 views)

Re: [FishMonger] need help removing charactors from string [In reply to]	Can't Post

not quite sure how to do that as i borrowed this code from a google search

FishMonger
Veteran / Moderator

Jun 9, 2012, 9:51 AM

Post #6 of 14 (2663 views)

Re: [gerble1000] need help removing charactors from string [In reply to]	Can't Post

Rather than simply copying something from the internet without knowing what it does, you should learn about regular expressions.

Start by reading the related perldoc's

http://perldoc.perl.org/perlrequick.html
http://perldoc.perl.org/perlretut.html
http://perldoc.perl.org/perlrecharclass.html

There are a couple others, but that will get you started.

It would also be a good idea to pick up a copy of Mastering Regular Expressions, 3rd Edition
http://shop.oreilly.com/product/9780596528126.do?green=17242849862&intcmp=af-mybuy-9780596528126.IP

gerble1000
User

Jun 10, 2012, 2:49 AM

Post #7 of 14 (2555 views)

Re: [FishMonger] need help removing charactors from string [In reply to]	Can't Post

ok i have read the first link.
does this look ok
$message =~ s/[^a-zA-Z0-9\077\100\040\047\050\051\054\055\056]*//g;

\077\100
are octal codes for ? and @
i am assuming this will work.

i have learned that ^ finds everything except what follows.
~ matches and the * repeats till the end s will search and replace and the /g

gerble1000
User

Jun 10, 2012, 3:08 AM

Post #8 of 14 (2550 views)

Re: [gerble1000] need help removing charactors from string [In reply to]	Can't Post

ok it seems to error out somewhere
this is the charactor causing all the problems
� � � � � �

gerble1000
User

Jun 10, 2012, 4:24 AM

Post #9 of 14 (2540 views)

Re: [gerble1000] need help removing charactors from string [In reply to]	Can't Post

ok i have it working now with this code
$message1 =~ s/[^a-zA-Z0-9\ \o{077}{100}{040}{047}{050}{051}{054}{055}{056}]*//g;
is this how you would have gone about doing it

FishMonger
Veteran / Moderator

Jun 10, 2012, 8:15 AM

Post #10 of 14 (2518 views)

Re: [gerble1000] need help removing charactors from string [In reply to]	Can't Post

I'd start with this and adjust if needed.

$message =~ /[^-?@ ',.A-Za-z0-9]+//g;

gerble1000
User

Jun 11, 2012, 2:09 AM

Post #11 of 14 (2504 views)

Re: [FishMonger] need help removing charactors from string [In reply to]	Can't Post

also on another note, how would you go about checking a file for a sentence with an if else statement. as this is what i have but only does a word and not a sentance.

open(FILE,"result.txt");
if (grep{/word/} <FILE>){
close FILE;
print "word found";
}
else{
close FILE;
print "not found";
}

instead of "word" i would like to have "word to look for"
i have tried this if (grep{/word\ to\ look\ for/}
but does not seem to work.
what am i doing wrong :)

BillKSmith
Veteran

Jun 13, 2012, 7:18 AM

Post #12 of 14 (2421 views)

Re: [gerble1000] need help removing charactors from string [In reply to]	Can't Post

It does work for me. Perhaps you could post a sample of the data that it should match but does not. Is part of the phrase on one line and rest on another?
Good Luck,
Bill

gerble1000
User

Jun 16, 2012, 7:35 AM

Post #13 of 14 (1926 views)

Re: [BillKSmith] need help removing charactors from string [In reply to]	Can't Post

your right that does work :)
but i can not do this

Code

if ((grep{/Message\ Sent\ Successfully/} <FILE>) || (grep{/Your\ message\ has\ been\ sent/} <FILE>)){ 
close FILE; 
open(F, '>>:utf8', 'sentchecktest.txt'); 
print F "sent\n"; 
close F; 
} 
 
else{ 
close FILE; 
open(F, '>>:utf8', 'sentchecktest.txt'); 
print F "error\n"; 
close F; 
}

i would have used an elsif but it does not work on my version of perl "strange"

gerble1000
User

Jun 17, 2012, 7:00 AM

Post #14 of 14 (1884 views)

Re: [gerble1000] need help removing charactors from string [In reply to]	Can't Post

sorted it
if (grep{/Message\ Sent\ Successfully/ || /Your\ message\ has\ been\ sent/} <FILE>){

Search for (options)

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