Learning MySQL

The Perl CGI Module

The Perl CGI module has some helpful functions to simplify generating common snippets of HTML. We can enable all these by modifying our use statement to:

use CGI ':all'

We can then generate HTML elements by calling the corresponding function. For example, we can include text within a level-one heading tag pair (<h1>text</h1>) by writing h1("text").

Many of these functions take attributes that are reflected in the generated HTML. For example, to generate the tag <th align="LEFT" bgcolor="SKYBLUE">, we would write:

th({-align=>"LEFT", -bgcolor=>"SKYBLUE"}, $Name).

Example 18-3 rewrites our our previous example using CGI functions.

Example 18-3. The CGI Animal list script rewritten with CGI functions

#!/usr/bin/perl
use strict;

# Connect to the MySQL server, run the query, store the result
use DBI;
my $dbh=DBI->connect("DBI:mysql:host=localhost;database=AnimalDB",
 "the_username",
 "the_password", {PrintError=>0, RaiseError=>1}); my $results = $dbh->selectall_hashref('SELECT * FROM Animals', 'Name'); $dbh->disconnect(); # Prepare and display the results in HTML format use CGI ':all'; my @AnimalsDataArray; foreach my $Name (keys %$results) { my $AnimalsDataArrayRow = th({-align=>"LEFT", -bgcolor=>"SKYBLUE"}, $Name). td({-bgcolor=>"PINK"}, [$results->{$Name}->{Count}]); push @AnimalsDataArray, $AnimalsDataArrayRow; } my $result= header(-type=>"text/html", -charset=>'UTF-8'). start_html(-title=>"List of Animals", -encoding => 'UTF-8'). h1("Pet roll call"). table( {-border=>'true'}, ...