Unsupported System Functions in Windows Forms

Most PowerBuilder system functions are supported in Windows Forms applications.

This table lists categories of system functions that are not supported.

Unsupported system functions by category
Category	Functions
DDE functions	CloseChannel, ExecRemote, GetCommandDDE, GetCommandDDEOrigin, GetDataDDE, GetDataDDEOrigin, GetRemote, OpenChannel, RespondRemote, SetDataDDE, SetRemote, StartHotLink, StartServerDDE, StopHotLink, StopServerDDE
Garbage collection functions	GarbageCollectGetTimeLimit, GarbageCollectSetTimeLimit
Miscellaneous functions	PBGetMenuString
Input method functions	IMEGetCompositionText, IMEGetMode, IMESetMode
Profiling and tracing functions	TraceBegin, TraceClose, TraceDisableActivity, TraceDump, TraceEnableActivity, TraceEnd, TraceError, TraceOpen, TraceUser

Post function

Post function calls with reference parameters are not supported.

IsNull function

In .NET applications, if you call the IsNull function with a variable of a reference type (a type derived from the PowerObject base class) as the argument, IsNull returns true when the variable has not been initialized by assigning an instantiated object to it. To ensure consistent behavior between standard and .NET PowerBuilder applications, use the IsValid function to check whether the variable has been instantiated.