# XML::Handler::Subs - a PerlSAX handler base class for calling user-defi... - perldoc - [phpMan]

## NAME
    [XML::Handler::Subs](https://www.chedong.com/phpMan.php/perldoc/XML%3A%3AHandler%3A%3ASubs/markdown) - a PerlSAX handler base class for calling user-defined subs

## SYNOPSIS
     use [XML::Handler::Subs](https://www.chedong.com/phpMan.php/perldoc/XML%3A%3AHandler%3A%3ASubs/markdown);

     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](https://www.chedong.com/phpMan.php/perldoc/XML%3A%3AHandler%3A%3ASubs/markdown)" is a base class for PerlSAX handlers. "[XML::Handler::Subs](https://www.chedong.com/phpMan.php/perldoc/XML%3A%3AHandler%3A%3ASubs/markdown)" 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](https://www.chedong.com/phpMan.php/perldoc/XML%3A%3AHandler%3A%3ASubs/markdown) in this way is similar to [XML::Parser](https://www.chedong.com/phpMan.php/perldoc/XML%3A%3AParser/markdown)'s Subs style.

    [XML::Handler::Subs](https://www.chedong.com/phpMan.php/perldoc/XML%3A%3AHandler%3A%3ASubs/markdown) 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
    if an element-name method is called, they return 0 if no method was called.

    [XML::Handler::Subs](https://www.chedong.com/phpMan.php/perldoc/XML%3A%3AHandler%3A%3ASubs/markdown) does not implement any other PerlSAX handlers.

    [XML::Handler::Subs](https://www.chedong.com/phpMan.php/perldoc/XML%3A%3AHandler%3A%3ASubs/markdown) supports the following methods:

### new
        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
        Returns true if `$name' is equal to the name of the innermost currently opened element.

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

## AUTHOR
    Ken MacLeod, <ken@bitsko.slc.ut.us>

## SEE ALSO
### perl