extract from html

[Lydia Shawn]

hi,
how can i extract the number between text1 and text2 in input.html
only the first time it occurs ignoring the rest?
preferably input.html would be a URL that stops downloading once a
match has occured, that would save a lot of bandwidth..
i guess html::parser would provide an option to work with a file while
it's downloading (?)

example
----

input.html:

bla..
text1 555 text2
bla
bla
text1 6000 text2
bla
EOF


output.txt
555


thanks for your help,
peter

[Simon Taylor]

Hello Peter,

> how can i extract the number between text1 and text2 in input.html
> only the first time it occurs ignoring the rest?
> preferably input.html would be a URL that stops downloading once a
> match has occured, that would save a lot of bandwidth..
> i guess html::parser would provide an option to work with a file while
> it's downloading (?)
>
> example
> ----
>
> input.html:
>
> bla..
> text1 555 text2
> bla
> bla
> text1 6000 text2
> bla
> EOF
>
>
> output.txt
> 555

Assuming you mean 'text1' and 'text2' are html tags, then the following
example, (which is straight out of the HTML::Parser documentation), will
do it for you. This example prints out the title text of a html page if
you supply the page as a filename on the command line, so just change
the word "title" to the tag name you require:


#!/usr/bin/perl

use strict;
use warnings;
use HTML::Parser ();

sub start_handler
{
return if shift ne "title";
my $self = shift;
$self->handler(text => sub { print shift }, "dtext");
$self->handler(end => sub { shift->eof if shift eq "title"; },
"tagname,self");
}

my $p = HTML::Parser->new(api_version => 3);
$p->handler( start => \&start_handler, "tagname,self");
$p->parse_file(shift || die) || die $!;
print "\n";

[Tad McClellan]

[ comp.lang.perl is not a Newsgroup. Removed ]


Lydia Shawn <apfeloma@hotmail.com> wrote:

> Subject: extract from html

Your post is not about extracting from HTML at all, so that
seems a strange choice of Subject...

> how can i extract the number between text1 and text2 in input.html
> only the first time it occurs ignoring the rest?

> input.html:
>
> bla..
> text1 555 text2
> bla
> bla
> text1 6000 text2
> bla
> EOF

No HTML there!

If you read it all into a scalar, then you can just do this pattern
match on the scalar:

/text1 (.*?) text2/


--
Tad McClellan SGML consulting
[email]tadmc@augustmail.com[/email] Perl programming
Fort Worth, Texas

[Michael Korte]

"Lydia Shawn" <apfeloma@hotmail.com> schrieb im Newsbeitrag
news:1240b4dc.0308051647.685dde59@posting.google.c om...

> hi,
> how can i extract the number between text1 and text2 in input.html
> only the first time it occurs ignoring the rest?

This problem I would solve by using a Hash. You can just put a unique key
into it, while finding the same term
it will be overwritten, or you can ask the hash if the term already exist

# $term is taken from your text - inbeetween text1 / text2
if( exists $myHash{$term})
{
# ignore
}else
{
$myHash{$term} = $value;
}

The Rest of your question : I don´t know ... sorry

> thanks for your help,
> peter

no prob...but what is your real name ?
"Lydia Shawn" or Peter :-)

HTH
greets Michael

[Lydia Shawn]

> Your post is not about extracting from HTML at all, so that

> seems a strange choice of Subject...
>

>>

> No HTML there!
>
> If you read it all into a scalar, then you can just do this pattern
> match on the scalar:
>
> /text1 (.*?) text2/

yes there is no html in my example,
my question is more about the function of html::parser working with a
file and matching things as the file is coming in, and stopping after
the first match has occured.. to prevent needless downloading. how can
i do that?
thanks a lot,
peter

[Lydia Shawn]

>

> Assuming you mean 'text1' and 'text2' are html tags, then the following
> example, (which is straight out of the HTML::Parser documentation), will
> do it for you. This example prints out the title text of a html page if
> you supply the page as a filename on the command line, so just change
> the word "title" to the tag name you require:
>
>

thanks simon,
but the text1/text2 is actual text that occur within <TD> tags which
are all over the document...
the reason i would like to use html::parser to do the job is its
feature, at least the way i understand it, to start matching things
before the whole file is read in. then, after the match, it should
stop in order to save bandwidth,
thaks again,
peter

[Brian Helterline]

"Lydia Shawn" <apfeloma@hotmail.com> wrote in message
news:1240b4dc.0308051647.685dde59@posting.google.c om...

> hi,
> how can i extract the number between text1 and text2 in input.html
> only the first time it occurs ignoring the rest?
> preferably input.html would be a URL that stops downloading once a
> match has occured, that would save a lot of bandwidth..
> i guess html::parser would provide an option to work with a file while
> it's downloading (?)

Take a look at the lwp-download script (in your perl bin directory)
as an example of a program that incrementally downloads a URL.
You can then search the contents for your text1 and text2 and stop if found.

The script uses LWP::UserAgent to do the download.

--
brian