ISNOTHING function

Purpose

Determine the current status of a given object variable.

Syntax

oStatus = ISNOTHING(objectvar)

Remarks

ISNOTHING is particularly useful in determining the success or failure of a LET statement.  It returns TRUE (-1) if the object variable contains nothing, or FALSE (0) if it contains a valid current reference to an object interface.

ISNOTHING is the complement to the ISOBJECT function.

Restrictions

objectvar must be an Interface or IDispatch object variable.

See also

DIM, INTERFACE (Direct), INTERFACE (IDBind), ISOBJECT, LET (with Objects), OBJECT, What is an object, anyway?

Example

DIM oApp AS IAPPDatabase

LET oApp = NEW IAPPDatabase IN "DBApp.0"

IF ISNOTHING(oApp) OR ERR THEN ...