/ 
ASP4-1.021
River stage one • 4 direct dependents • 4 total dependents
/ ASP4::MasterPage

NAME

ASP4::MasterPage - Root class for MasterPage classes.

SYNOPSIS

In your ASP script (/eg-master.asp):

<%@ MasterPage %>
<html>
  <body>
    <h1><asp:ContentPlaceHolder id="heading">Default Heading</asp:ContentPlaceHolder></h1>
    <p>
      <asp:ContentPlaceHolder id="content">Default Content</asp:ContentPlaceHolder>
    </p>
  </body>
</html>

It gets compiled down to:

package MyApp::_eg_master_asp;

use strict;
use warnings 'all';
no warnings 'redefine';
use base 'ASP4::MasterPage';
use vars __PACKAGE__->VARS;
use ASP4::PageLoader;

sub _init {
  my ($s) = @_;
  $s->{script_name} = q</eg-master.asp>;
  $s->{filename}    = q</home/john/Projects/www.example.com/htdocs/eg-master.asp>;
  $s->{base_class}  = q<ASP4::MasterPage>;
  $s->{compiled_as} = q<MyApp/_eg_master_asp.pm>;
  $s->{package}     = q<MyApp::_eg_master_asp>;

  return;
}

sub run {
use warnings 'all';
my ($__self, $__context) = @_;
#line 1
;$Response->Write(q~
<html>
  <body>
    <h1>~); $__self->heading($__context); $Response->Write(q~</h1>
    <p>
      ~); $__self->content($__context); $Response->Write(q~
    </p>
  </body>
</html>
~);
}

sub heading {
my ($__self, $__context) = @_;
#line 4
$Response->Write(q~Default Heading~);
}# end heading

sub content {
my ($__self, $__context) = @_;
#line 6
$Response->Write(q~Default Content~);
}# end content

1;# return true:

Which, when executed, produces:

<html>
  <body>
    <h1>Default Heading</h1>
    <p>
      Default Content
    </p>
  </body>
</html>

But Wait - There's More!

MasterPages only get interesting when we add "child" pages to them:

(/eg-child.asp)

<%@ Page UseMasterPage="/eg-master.asp" %>

<asp:Content PlaceHolderID="heading">New Heading</asp:Content>

<asp:Content PlaceHolderID="content">New Content</asp:Content>

Which compiles down to:

package MyApp::_eg_child_asp;

use strict;
use warnings 'all';
no warnings 'redefine';
use base 'MyApp::_eg_master_asp';
use vars __PACKAGE__->VARS;
use ASP4::PageLoader;

sub _init {
  my ($s) = @_;
  $s->{script_name} = q</eg-child.asp>;
  $s->{filename}    = q</home/john/Projects/www.example.com/htdocs/eg-child.asp>;
  $s->{base_class}  = q<MyApp::_eg_master_asp>;
  $s->{compiled_as} = q<MyApp/_eg_child_asp.pm>;
  $s->{package}     = q<MyApp::_eg_child_asp>;
  $s->{masterpage}  = ASP4::PageLoader->load( script_name => q</eg-master.asp> );
  return;
}

sub heading {
my ($__self, $__context) = @_;
#line 3
$Response->Write(q~New Heading~);
}# end heading

sub content {
my ($__self, $__context) = @_;
#line 5
$Response->Write(q~New Content~);
}# end content

1;# return true:

And when executed produces:

<html>
  <body>
    <h1>New Heading</h1>
    <p>
      New Content
    </p>
  </body>
</html>

And Even More!

Child pages can also be master pages:

(/eg-subpage.asp):

<%@ MasterPage %>
<%@ Page UseMasterPage="/eg-master.asp" %>

<asp:Content PlaceHolderID="heading">New Heading</asp:Content>

<asp:Content PlaceHolderID="content">
  New Content
  <span id="copyright">
    Copyright
    <asp:ContentPlaceHolder id="copyright"></asp:ContentPlaceHolder>: 
    All Rights Reserved
  </span>
</asp:Content>

And inherited from again:

(/eg-subchild.asp):

<%@ Page UseMasterPage="/eg-master.asp" %>

<asp:Content PlaceHolderID="copyright">SuperMegaCorp, Inc.</asp:Content>

Which - when executed, produces:

<html>
  <body>
    <h1>New Heading</h1>
    <p>
      
  New Content
  <span id="copyright">
    Copyright
    SuperMegaCorp, Inc.:
    All Rights Reserved
  </span>

    </p>
  </body>
</html>

DESCRIPTION

MasterPages provide a means of rich page composition. This means that instead of a tangle of server-side includes, you can actually take advantage of this new concept (came out decades ago) called "class inheritance" - and apply it to your web pages.