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Extract data from a saved file

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Join Date: May 2008

Posts: 128

Reputation: kenji is an unknown quantity at this point

Solved Threads: 9

kenji

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Junior Poster

Extract data from a saved file

May 13th, 2009

Hey,

I have used the LWP:\

imple module and saved the source of a website in a file. I am trying to extract all the data between the <head> tags and pass it to a variable to process.

So far I can't seem to extract the data properly. Any suggestions?

 Help with Code Tags 
 Perl Syntax (Toggle Plain Text) 
my $data = getstore("http://www.google.com/", "website.txt");
unless(is_success($data)){
	die "Could not retrive website: $data";
}
open(PAGE, "website.txt") or die "$!";
my @info = <PAGE>;
close(PAGE);
my @meta;
my $i = 0;
my $stuff;
foreach $stuff(@info){
	$meta[$i] = ($stuff =~ m/<head(.*?)</head>/);
	$i++;
}
$i = 0;
foreach $_ (@meta){
	#print $meta[$i];
	print $_;
}
my $data = getstore("http://www.google.com/", "website.txt");
unless(is_success($data)){
	die "Could not retrive website: $data";
}
open(PAGE, "website.txt") or die "$!";
my @info = <PAGE>;
close(PAGE);
my @meta;
my $i = 0;
my $stuff;
foreach $stuff(@info){
	$meta[$i] = ($stuff =~ m/<head(.*?)</head>/);
	$i++;
}
$i = 0;
foreach $_ (@meta){
	#print $meta[$i];
	print $_;
}

Thanks

Last edited by kenji; May 13th, 2009 at 4:07 pm.

And she said "Let there be light" and on the seveth day Windows booted.
And the crowds screamed in terror and cowered in fear for Microsoft had approached.
From the testament of 10011101

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Join Date: May 2008

Posts: 128

Reputation: kenji is an unknown quantity at this point

Solved Threads: 9

kenji

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Junior Poster

Re: Extract data from a saved file

May 13th, 2009

UPDATE:

I managed to get the data into one string and now I am trying to match with a regular expression.

I am having trouble with the regular expression.

 Help with Code Tags 
 Perl Syntax (Toggle Plain Text) 
my $d = ($s =~ m/<head>(.*)<\/head>/);
my $d = ($s =~ m/<head>(.*)<\/head>/);

$s is the scalar with the whole string, I want to extract the head tag s from $s and assign to $d.

And she said "Let there be light" and on the seveth day Windows booted.
And the crowds screamed in terror and cowered in fear for Microsoft had approached.
From the testament of 10011101

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Join Date: Mar 2006

Posts: 898

Reputation: KevinADC has a spectacular aura about

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KevinADC

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Re: Extract data from a saved file

May 13th, 2009

try:

my ($d) = $s =~ m/<head>(.*?)<\/head>/is;

Last edited by KevinADC; May 13th, 2009 at 7:35 pm.

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Join Date: May 2008

Posts: 128

Reputation: kenji is an unknown quantity at this point

Solved Threads: 9

kenji

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Junior Poster

Re: Extract data from a saved file

May 13th, 2009

Thanks that worked great.

What exactly does /is do? Also one more question if I try to extract the meta tags and place each individually in array will it work? Assuming that their maybe 1 or meta tags inside.

Something like this:
my (@m) = $s =~ m/<meta (.*?)>/is;

Last edited by kenji; May 13th, 2009 at 8:30 pm.

And she said "Let there be light" and on the seveth day Windows booted.
And the crowds screamed in terror and cowered in fear for Microsoft had approached.
From the testament of 10011101

•

Join Date: May 2008

Posts: 128

Reputation: kenji is an unknown quantity at this point

Solved Threads: 9

kenji

Offline

Junior Poster

Re: Extract data from a saved file

May 13th, 2009

This is what I came up with, but it seems to be repeating the first match rather than check for the next meta tag.

 Help with Code Tags 
 Perl Syntax (Toggle Plain Text) 
my (@m) = $d =~ m/(<meta (.*?)>){1,5}/is;
my (@m) = $d =~ m/(<meta (.*?)>){1,5}/is;

And she said "Let there be light" and on the seveth day Windows booted.
And the crowds screamed in terror and cowered in fear for Microsoft had approached.
From the testament of 10011101

•

Join Date: Mar 2006

Posts: 898

Reputation: KevinADC has a spectacular aura about

Solved Threads: 67

KevinADC

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Practically a Posting Shark

Re: Extract data from a saved file

May 14th, 2009

my (@m) = $s =~ m/<meta (.*?)>/gis;

You can look up the regexp modifiers in any regexp tutorial.

i - case insentive matching
s - match as a single string so matches across newlines
g - global match, works like grep, finds all matches in a string/line

Last edited by KevinADC; May 14th, 2009 at 6:02 am.