Class CustomFields

This class deals with custom fields in general, as opposed to custom fields concerning a specific object.

WPGMZA\CustomFields implements IteratorAggregate, JsonSerializable, Countable

Namespace: WPGMZA
Located at custom-fields/class.custom-fields.php

Methods summary
`public`	# `__construct( $map_id = null )`
`public static`	# `install( )` Installs the DB tables for custom fields Installs the DB tables for custom fields
`public static boolean`	# `installed( )` Returns true if the custom fields tables are installed, caches the result of the DB query for performance. TODO: Modify this to count instead so that adding polygon tables etc. will be done Returns true if the custom fields tables are installed, caches the result of the DB query for performance. TODO: Modify this to count instead so that adding polygon tables etc. will be done Returns boolean
`public ArrayIterator`	# `getIterator( )` Get iterator for looping over fields with foreach Get iterator for looping over fields with foreach Returns ArrayIterator Implementation of `IteratorAggregate::getIterator()`
`public array`	# `jsonSerialize( )` Gets the fields to be serialized as JSON, useful for export Gets the fields to be serialized as JSON, useful for export Returns array Implementation of `JsonSerializable::jsonSerialize()`
`public`	# `count( )` Implementation of `Countable::count()`