Represents a variable in the system. Variables are a convenient way to advertise arbitrary state to other parts of the system.

Autodesk.AutoCAD.Runtime.DisposableWrapper
    Autodesk.AutoCAD.Runtime.Variable

Public Class Variable
Inherits DisposableWrapper

public class Variable : DisposableWrapper;

Variables are created by declaring them in the registry. The following format should be used (elements between {} should be replaced with a legal value for the property or type indicated inside the {}). 

[HKEY_LOCAL_MACHINE{ProductRegistryRoot}Variables{AcRxVariable::name()}] @="{some value}" : Required, will be converted to PrimaryDataType "PrimaryType"=dword:{AcRxVariable::primaryType()} : Required "SecondaryType"=dword:{AcRxVariable::seondaryType()} : Optional "TypeFlags"=dword:{AcRxVariable::typeFlags()} : Optional "StorageType"=dword:{AcRxVariable::StorageType} : Required "Owner"="{LogicalAppName|exe}" : Optional "Range"="{lowerbound},{upperbound}" : Optional, applies to RTREAL, RTANG, RTSHORT and RTLONG primary types 

Note these variables can be get/set using acedGetVar/acedSetVar functions in AutoCAD. They are also visible to the SETVAR command.