Working with Value Representations

The value representation of a data element indicates the type of data that can be stored in the value field of the data element. There are a number of value representations that are standard for the DICOM file format. In addition to the standard value representations, user-defined value representations may also be added.

LEADTOOLS maintains a table (or list) internally of all available value representations, standard and user defined. In this documentation the table of available value representations will be referred to as the Value Representation Table. Also provided in this documentation is a table of the default values for the standard value representations. To see these default values, refer to the Default Value Representation Table.

LEADTOOLS provides a number of methods for maneuvering through and modifying the Value Representation Table. All methods pertaining to the Value Representation Table have the form xxxVR method or xxxVRxxx method.

For maneuvering through the Value Representation Table, LEADTOOLS provides the following methods:

MoveFirstVR method

MoveLastVR method

MovePrevVR method

MoveNextVR method

GetVRCount method

To find specific items, based on either the value representation or an index into the table, use the FindVR method and the FindIndexVR method.

To insert new items in the Value Representation Table, use the InsertVR method.

You can delete individual items from the table using the DeleteVR method, or you can delete all items from the table, using the ResetVR method.

To change the name of an item already in the table, use the SetVRName method.

Finally, to reset the Value Representation Table to the default values, use the DefaultVR method.

Whenever you access an item within the Value Representation Table, the CurrentVR property is updated with the selected item.

For more information on value representations, refer to An Overview of the DICOM File Format or the DICOM Standard.