SYNOPSIS
# Create an object for a content-type field:
$field = new Mail::Field 'Content-type';
# Set some attributes:
$field->param('_' => 'text/html');
$field->param('charset' => 'us-ascii');
$field->param('boundary' => '---ABC---');
# Same:
$field->set('_' => 'text/html',
'charset' => 'us-ascii',
'boundary' => '---ABC---');
# Get an attribute, or undefined if not present:
print "no id!" if defined($field->param('id'));
# Same, but use empty string for missing values:
print "no id!" if ($field->paramstr('id') eq '');
# Output as string:
print $field->stringify, "\n";
DESCRIPTION
This is an abstract superclass of most MIME fields. It handles fields with a general syntax like this:
Content-Type: Message/Partial; number=2; total=3; id="[email protected]"
Comments are supported between items, like this:
Content-Type: Message/Partial; (a comment) number=2 (another comment) ; (yet another comment) total=3; id="[email protected]"
PUBLIC INTERFACE
- set [\%PARAMHASH | KEY=>VAL,...,KEY=>VAL]
-
Instance method. Set this field.
The paramhash should contain parameter names
in all lowercase, with the special "_" parameter name
signifying the ``default'' (unnamed) parameter for the field:
# Set up to be... # # Content-type: Message/Partial; number=2; total=3; id="ocj=pbe0M2" # $conttype->set('_' => 'Message/Partial', 'number' => 2, 'total' => 3, 'id' => "ocj=pbe0M2");
Note that a single argument is taken to be a reference to a paramhash, while multiple args are taken to be the elements of the paramhash themselves.
Supplying undef for a hashref, or an empty set of values, effectively clears the object.
The self object is returned.
- parse_params STRING
-
Class/instance utility method.
Extract parameter info from a structured field, and return
it as a hash reference. For example, here is a field with parameters:
Content-Type: Message/Partial; number=2; total=3; id="[email protected]"
Here is how you'd extract them:
$params = $class->parse_params('content-type'); if ($$params{'_'} eq 'message/partial') { $number = $$params{'number'}; $total = $$params{'total'}; $id = $$params{'id'}; }
Like field names, parameter names are coerced to lowercase. The special '_' parameter means the default parameter for the field.
NOTE: This has been provided as a public method to support backwards compatibility, but you probably shouldn't use it.
- parse STRING
-
Class/instance method.
Parse the string into the instance. Any previous information is wiped.
The self object is returned.
May also be used as a constructor.
- param PARAMNAME,[VALUE]
- Instance method. Return the given parameter, or undef if it isn't there. With argument, set the parameter to that VALUE. The PARAMNAME is case-insensitive. A ``_'' refers to the ``default'' parameter.
- paramstr PARAMNAME,[VALUE]
- Instance method. Like param(): return the given parameter, or empty if it isn't there. With argument, set the parameter to that VALUE. The PARAMNAME is case-insensitive. A ``_'' refers to the ``default'' parameter.
- stringify
- Instance method. Convert the field to a string, and return it.
- tag
- Instance method, abstract. Return the tag for this field.