To use some variable methods, such as the Find Descendants and Is Kind Of methods, you must specify the Class Identifier of a Variable class with the Class Identifier input. The following table shows the Class Identifiers of the Variable classes included in LabVIEW.
| Class Name | Class Identifier |
|---|---|
| Variable Object | VariableObject |
| Variable | Variable |
| PSP Variable | PSPVariable |
| I/O Variable | IOVariable |
| Variable | Variable |
| Variable Container | VariableContainer |
| PSP Variable Container | PSPVariableContainer |
| I/O Variable Container | IOVariableContainer |
| Variable Engine | VariableEngine |
| PSP Variable Engine | PSPVariableEngine |
| I/O Variable Engine | IOVariableEngine |
You also can use the Class Identifier property of any class that inherits from Variable Object to obtain the Class Identifier programmatically. For example, in the following figure, the Class Identifier property passes the Class Identifier of the PSP Variable Container to the Find Descendants method. The Find Descendants method then returns an array of references to the PSP variable containers on the local host.