Refnum Controls and IndicatorsDownload PDFSelected SectionSelected Section and Subsection(s)Entire ManualUpdated2026-05-291 minute(s) readLabVIEWUser Manual Use the reference number controls on the Refnum palette to work with files, directories, devices, and network connections in your VIs. Use the different available types of refnum controls when you want to pass a refnum into or out of a VI. Refnums in LabVIEWA reference number, or refnum, is a unique identifier that LabVIEW creates for an open object, such as a file, device, or network connection. Refnums identify objects for operations while the objects remain open.Types of Refnum ControlsThere are different types of refnums in LabVIEW for different types of objects. Some refnums are available directly from the Controls palette, while others are available from the specific objects that use those refnums.Creating Strictly Typed RefnumsStrictly typed VI refnums have data type information that includes the connector pane of the VI. Use strictly typed refnums to communicate with certain functions and to enforce the data type of the control.Switching Between Strictly Typed and Weakly Typed Control RefnumsStrictly typed control refnums accept only control refnums of exactly the same data type. Weakly typed control refnums are more flexible in the type of data they accept.Parent topic: Front Panel Controls and Indicators
Use the reference number controls on the Refnum palette to work with files, directories, devices, and network connections in your VIs. Use the different available types of refnum controls when you want to pass a refnum into or out of a VI. Refnums in LabVIEWA reference number, or refnum, is a unique identifier that LabVIEW creates for an open object, such as a file, device, or network connection. Refnums identify objects for operations while the objects remain open.Types of Refnum ControlsThere are different types of refnums in LabVIEW for different types of objects. Some refnums are available directly from the Controls palette, while others are available from the specific objects that use those refnums.Creating Strictly Typed RefnumsStrictly typed VI refnums have data type information that includes the connector pane of the VI. Use strictly typed refnums to communicate with certain functions and to enforce the data type of the control.Switching Between Strictly Typed and Weakly Typed Control RefnumsStrictly typed control refnums accept only control refnums of exactly the same data type. Weakly typed control refnums are more flexible in the type of data they accept.Parent topic: Front Panel Controls and Indicators
Use the reference number controls on the Refnum palette to work with files, directories, devices, and network connections in your VIs. Use the different available types of refnum controls when you want to pass a refnum into or out of a VI. Refnums in LabVIEWA reference number, or refnum, is a unique identifier that LabVIEW creates for an open object, such as a file, device, or network connection. Refnums identify objects for operations while the objects remain open.Types of Refnum ControlsThere are different types of refnums in LabVIEW for different types of objects. Some refnums are available directly from the Controls palette, while others are available from the specific objects that use those refnums.Creating Strictly Typed RefnumsStrictly typed VI refnums have data type information that includes the connector pane of the VI. Use strictly typed refnums to communicate with certain functions and to enforce the data type of the control.Switching Between Strictly Typed and Weakly Typed Control RefnumsStrictly typed control refnums accept only control refnums of exactly the same data type. Weakly typed control refnums are more flexible in the type of data they accept.Parent topic: Front Panel Controls and Indicators