Differences Between Ring Controls and Enum Controls

Ring controls and enumerated type (enum) controls in LabVIEW both contain lists of strings that a user can cycle through, where each string is associated with a number. However, they differ in a few key ways.

Understand the differences to decide whether to use a ring control or an enum control.

Table 14. Ring Control and Enum Control Differences
Characteristic Ring Control Behavior Enum Control Behavior
Data type Data type is numeric only. Data type includes information about both the numeric values in the control and about their corresponding strings.
Numeric representation[1]1 To change the representation of a ring or an enum, right-click either type of control and select Representation. Wider variety of representations. 8-, 16-, or 32-bit unsigned integer only.
Item type Includes controls that can support strings, pictures, and a combination of strings and pictures. Supports strings only.
Undefined values Users can enter undefined values. Not supported: users must choose a specific item.
Arbitrary numbering Supports arbitrary numbering of items in the control. Not supported: numbering associated with items in the control is always sequential.
Editing items in the control at run time Supported using a Property Node. Not supported: edit enum controls only at edit time.
Case Structure: how LabVIEW identifies cases LabVIEW matches cases to the numeric values of items in the ring control. LabVIEW matches cases to the string values of items in the enum control.
Case Structure: how to create cases You must manually create a case for each item in the ring control. You can create cases for all items in the enum control at once: right-click the structure and select Add Case for Every Value.

1 To change the representation of a ring or an enum, right-click either type of control and select Representation.