xml::handler::subs(3) [centos man page]

XML::Handler::Subs(3)					User Contributed Perl Documentation				     XML::Handler::Subs(3)

NAME

       XML::Handler::Subs - a PerlSAX handler base class for calling user-defined subs

SYNOPSIS

	use XML::Handler::Subs;

	package MyHandlers;
	use vars qw{ @ISA };

	sub s_NAME { my ($self, $element) = @_ };
	sub e_NAME { my ($self, $element) = @_ };

	$self->{Names};    # an array of names
	$self->{Nodes};    # an array of $element nodes

	$handler = MyHandlers->new();
	$self->in_element($name);
	$self->within_element($name);

DESCRIPTION

       "XML::Handler::Subs" is a base class for PerlSAX handlers.  "XML::Handler::Subs" is subclassed to implement complete behavior and to add
       element-specific handling.

       Each time an element starts, a method by that name prefixed with `s_' is called with the element to be processed.  Each time an element
       ends, a method with that name prefixed with `e_' is called.  Any special characters in the element name are replaced by underscores.

       Subclassing XML::Handler::Subs in this way is similar to XML::Parser's Subs style.

       XML::Handler::Subs maintains a stack of element names, `"$self-"{Names}', and a stack of element nodes, `"$self-"{Nodes}>' that can be used
       by subclasses.  The current element is pushed on the stacks before calling an element-name start method and popped off the stacks after
       calling the element-name end method.  The `"in_element()"' and `"within_element()"' calls use these stacks.

       If the subclass implements `"start_document()"', `"end_document()"', `"start_element()"', and `"end_element()"', be sure to use `"SUPER::"'
       to call the the superclass methods also.  See perlobj(1) for details on SUPER::.  `"SUPER::start_element()"' and `"SUPER::end_element()"'
       return 1 if an element-name method is called, they return 0 if no method was called.

       XML::Handler::Subs does not implement any other PerlSAX handlers.

       XML::Handler::Subs supports the following methods:

       new( OPTIONS )
	   A basic `"new()"' method.  `"new()"' takes a list of key, value pairs or a hash and creates and returns a hash with those options; the
	   hash is blessed into the subclass.

       in_element($name)
	   Returns true if `$name' is equal to the name of the innermost currently opened element.

       within_element($name)
	   Returns the number of times the `$name' appears in Names.

AUTHOR

       Ken MacLeod, ken@bitsko.slc.ut.us

SEE ALSO

       perl(1), PerlSAX.pod(3)

perl v5.16.3							    2003-10-21						     XML::Handler::Subs(3)

XML::Handler::XMLWriter(3)				User Contributed Perl Documentation				XML::Handler::XMLWriter(3)

NAME

       XML::Handler::XMLWriter - a PerlSAX handler for writing readable XML

SYNOPSIS

	use XML::Parser::PerlSAX;
	use XML::Handler::XMLWriter;

	$my_handler = XML::Handler::XMLWriter->new( I<OPTIONS> );

	XML::Parser::PerlSAX->new->parse(Source => { SystemId => 'REC-xml-19980210.xml' },
					 Handler => $my_handler);

DESCRIPTION

       "XML::Handler::XMLWriter" is a PerlSAX handler for writing readable XML (in contrast to Canonical XML, for example).
       XML::Handler::XMLWriter can be used with a parser to reformat XML, with XML::DOM or XML::Grove to write out XML, or with other PerlSAX
       modules that generate events.

       "XML::Handler::XMLWriter" is intended to be used with PerlSAX event generators and does not perform any checking itself (for example,
       matching start and end element events).	If you want to generate XML directly from your Perl code, use the XML::Writer module.  XML::Writer
       has an easy to use interface and performs many checks to make sure that the XML you generate is well-formed.

       "XML::Handler::XMLWriter" is a subclass of "XML::Handler::Subs".  "XML::Handler::XMLWriter" can be further subclassed to alter it's
       behavior or to add element-specific handling.  In the subclass, each time an element starts, a method by that name prefixed with `s_' is
       called with the element to be processed.  Each time an element ends, a method with that name prefixed with `e_' is called.  Any special
       characters in the element name are replaced by underscores.  If there isn't a start or end method for an element, the default action is to
       write the start or end tag.  Start and end methods can use the `"print_start_element()"' and `"print_end_element()"' methods to print start
       or end tags.  Subclasses can call the `"print()"' method to write additional output.

       Subclassing XML::Handler::XMLWriter in this way is similar to XML::Parser's Stream style.

       XML::Handler::Subs maintains a stack of element names, `"$self-"{Names}', and a stack of element nodes, `"$self-"{Nodes}>' that can be used
       by subclasses.  The current element is pushed on the stacks before calling an element-name start method and popped off the stacks after
       calling the element-name end method.

       See XML::Handler::Subs for additional methods.

       In addition to the standard PerlSAX handler methods (see PerlSAX for descriptions), XML::Handler::XMLWriter supports the following methods:

       new( OPTIONS )
	   Creates and returns a new instance of XML::Handler::XMLWriter with the given OPTIONS.  Options may be changed at any time by modifying
	   them directly in the hash returned.	OPTIONS can be a list of key, value pairs or a hash.  The following OPTIONS are supported:

	   Output
	       An IO::Handle or one of it's subclasses (such as IO::File), if this parameter is not present and the AsString option is not used,
	       the module will write to standard output.

	   AsString
	       Return the generated XML as a string from the `"parse()"' method of the PerlSAX event generator.

	   Newlines
	       A true or false value; if this parameter is present and its value is true, then the module will insert an extra newline before the
	       closing delimiter of start, end, and empty tags to guarantee that the document does not end up as a single, long line.  If the
	       paramter is not present, the module will not insert the newlines.

	   IsSGML
	       A true or false value; if this parameter is present and its value is true, then the module will generate SGML rather than XML.

       print_start_element($element)
	   Print a start tag for `$element'.  This is the default action for the PerlSAX `"start_element()"' handler, but subclasses may use this
	   if they define a start method for an element.

       print_end_element($element)
	   Prints an end tag for `$element'.  This is the default action for the PerlSAX `"end_element()"' handler, but subclasses may use this if
	   they define a start method for an element.

       print($output)
	   Write `$output' to Output and/or append it to the string to be returned.  Subclasses may use this to write additional output.

TODO

       o   An Elements option that provides finer control over newlines than the Newlines option, where you can choose before and after newline
	   for element start and end tags.  Inspired by the Python XMLWriter.

       o   Support Doctype and XML declarations.

AUTHOR

       Ken MacLeod, ken@bitsko.slc.ut.us This module is partially derived from XML::Writer by David Megginson.

SEE ALSO

       perl(1), PerlSAX.pod(3)

perl v5.16.3							    2003-10-21						XML::Handler::XMLWriter(3)