'Declaration Public Class UltraCalcFunctionIsRef Inherits BuiltInFunctionBase
public class UltraCalcFunctionIsRef : BuiltInFunctionBase
ISREF( reference)
Reference is an UltraCalcValue object that contains a reference to some application-specific control, field, or piece of information. You can think of it as an address which the UltraCalc engine uses to look-up a value in your application when one is needed to evaluate an expression.
The ISREF function returns TRUE when the specified UltraCalcValue is a reference. Since it's value is defined by the contents at another referenced location, it's possible for this UltraCalcValue object to change in value based on changes in your application (outside of the UltraCalc engine.) Proper implementation of the IUltraCalcReference interface and NotifyValueChange methods will ensure the UltraCalc engine is made aware of any changes in a referenced value, and that all references depending on this value are refreshed.
Conversely, the ISREF function will return FALSE should the UltraCalcValue you supply represent a constant value or the temporary result of evaluating an UltraCalc expression (a constant value sitting at the top of the UltraCalc engine's number stack.)
Target Platforms: Windows 10, Windows 8.1, Windows 8, Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2