in reply to parse a changing html table

Don't listen to the insane ramblings of the Anonymous Monk.

If you have to work some HTML-file, your best bet is one of the parser modules such as HTML::Parser.

Looking at the structure of your HTML file, you will see that the info you are looking for is always contained within a a-tag and more specifically within the href-attribute in that tag.

With HTML::Parser it is trivially easy to extract all a-tags from the HTML file and then use a regex to see if the attribute contains the string 'CIS Report for followed by a date. Extracting the date and the filename is simple. You probably just want to extract the filename for the date of today. That is left as an exercise for you.

Here follows the basic program:

use strict; use HTML::Parser (); # Create parser object my $p = HTML::Parser->new( api_version => 3, start_h => [\&a_tag, "tag, attr"], ); $p->parse_file('c:/data/perl/script/volvo.html'); sub a_tag { my $tag = shift; return unless $tag eq 'a'; my $hashref = shift; return unless $hashref->{'href'}=~m|'CIS Report for (\d{2}/\d{2}/\ +d{4})|; my $date = $1; (my $file) = $hashref->{'href'}=~m|PopupInfo\('(.*pdf)|; print "$date: $file\n"; }
And it prints:
12/26/2007: CE1B85BDDDE8F58A852573BD003B1FBC/$file/vcmorarorp346601226 +200712262007944204.pdf 12/26/2007: CE1B85BDDDE8F58A852573BD003B1FBC/$file/vcmorarorp346601226 +200712262007944204.pdf 12/25/2007: C0FBD06860B80B7B852573BC003B3738/$file/vcmorarorp346601225 +200712252007939900.pdf 12/25/2007: C0FBD06860B80B7B852573BC003B3738/$file/vcmorarorp346601225 +200712252007939900.pdf 12/24/2007: 31ED64C95AFF1A06852573BB003F55E5/$file/vcmorarorp346601224 +200712242007930592.pdf 12/24/2007: 31ED64C95AFF1A06852573BB003F55E5/$file/vcmorarorp346601224 +200712242007930592.pdf
Remark: It seems each filename is mentioned twice in the HTML-page.

CountZero

A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James

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Re^2: parse a changing html table
by gary441 (Initiate) on Dec 29, 2007 at 14:04 UTC
    CountZero,
    First, thanks for all your help. I did figure out how to add in the date to help parse the correct info. And later today I will learn more about your code, but I understand most of it already. I do have more questions, but I rather read more and experiment, then I'll ask.

    Anon Monk,
    Don't worry, I intend to learn regex also. From what I read, it seems that I'd be better off learning both ways.

    Thanks Peeps, you both helped.
    Gary
      Ok, I've figured out how to add in today's date.
      Last night I studied your code and HTML::Parser, so I have a better understanding of both. Now I should be able to download the PDF file automatically every morning.
      Again, Thank You to everyone for the help and Thank You for taking the time to help.
      Should I post my code? I will if anyone thinks it will help someone else (and no one laughs). I will play around with regex. Thanks,
      Gary
Re^2: parse a changing html table
by Anonymous Monk on Dec 28, 2007 at 21:32 UTC
    I am the insane anon. why html::parser? can not he roll his own?
      If the axle on your car breaks, do you

        mine some iron ore

        smelt it

        cast a new axle (it better not be too short, or too long)

        install it

      Or do you go to your mechanic to have a new one installed?