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in reply to perl & Asynchronous Javascript

Greetings InfiniteLoop,

As I mention here and here, I'm a big fan of JSON (JavaScript Object Notation) and the JSON.pm module from CPAN. When used with CGI::Application, you just return the JSON-created string out of the subroutine that's setup by setup instead of your normal template content. It's crazy-simple.

Here's some sample code...

Here's a skeleton CGI::Application-inspired module. There are two run modes, one which is a fairly typical HTML::Template situation, and the other is the AJAX variety.

package YourCGIAppModule; use strict; use warnings; use JSON; use base 'CGI::Application'; sub cgiapp_init { my $self = shift; $self->param( 'json' => JSON->new ); } sub setup { my $self = shift; $self->start_mode('main'); $self->run_modes( 'main' => 'screen_main_page', 'random' => 'ajax_get_random', ); } sub screen_main_menu { my $self = shift; my $tmpl_obj = $self->load_tmpl( 'default.tmpl', 'loop_context_vars' => 1, ); $tmpl_obj->param( 'title' => 'Main Menu' ); return $tmpl_obj->output; } sub ajax_verify_browser { my $self = shift; return $self->param('json')->objToJson({ 'random' => rand }); }

I know this is really basic/simple, but it just doesn't have to be any more complicated than this. To get the data from JavaScript, you make the XMLHttpRequest object call and eval the returned text:

var randomNumber = eval('(' + ajaxJSONtext + ')');

gryphon
Whitepages.com Development Manager (DSMS)
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