Selecting specific tags, Tagfilter interface, Multifilter – ThingMagic Mercury API v1.23.0 User Manual
Page 39: Multifilter 39, Defines a subset of tags to search for, Antennas
Selecting Specific Tags
Level 2 API
39
Selecting Specific Tags
TagFilter Interface
TagFilter is an interface type that represents tag read filtering operation. Currently
classes which implement the TagFilter Interface provide two ways to filter tags:
1. Air Protocol Filtering - When specifying a TagFilter as parameter for
Advanced Tag Operations [Deprecated]
, the filter will be applied at the air
protocol level, i.e. to tags “in the field”. That is, only tags matching the
TagFilter
criteria will be returned in an inventory operation or operated (write, lock, etc.) on.
2. Post Inventory Filtering - Objects of type TagFilter provide a match() method
that can be used to check whether a
object matches the
TagFilter criteria.
This filtering is not applied to tags “in the field”.
Note
Currently, post inventory filtering with
match() can only be used to filter
against a
EPC value.
The
class implements the
TagFilter interface and TagData objects may be
used as such to match a tag with a specific EPC. The protocol specific classes:
, among others, represent the protocol selection
capabilities of their respective protocols and can be used to perform the protocol-specific
filtering operations. Applying a filter of one protocol to an operation of another protocol will
result in an error.
object can be used to create more elaborate filters from a list of simpler filters.
MultiFilters are not currently supported by any readers.
Any
TagFilter may match more than one tag in an operation; they do not guarantee
uniqueness.
Note
The Mercury4, Mercury5 and Astra readers currently only support
TagData
filters. They do not support
[Protocol].Select type TagFilters.
MultiFilter
Contains an array of objects that implement the
. When used as a
TagFilter the array of TagFilters in the MultiFilter object will be applied for tag
selection.