|
Parameter-Packing Functions
The lParam parameter of many DDE messages contains two pieces of data. For example, the lParam of the WM_DDE_DATA message contains a data handle and an atom. In previous versions of Windows,
an application could use the MAKELONG macro to prepare an lParam parameter, and the LOWORD and HIWORD macros to remove the low-order and high-order values from lParam. Because a Win32 data handle is a 32-bit value, a Win32-based application
must use the PackDDElParam function to pack the handle and atom into an lParam parameter, and the UnpackDDElParam function to remove the values. DDE applications must use PackDDElParam and UnpackDDElParam for all messages posted during a DDE conversation.
The Win32 API also includes the ReuseDDElParam and FreeDDElParam functions. ReuseDDElParam allows a DDE application to reuse a packed lParam parameter, helping reduce the number of memory reallocations the application
must perform during a conversation. An application can use FreeDDElParam to free the memory associated with a data handle received during a DDE
conversation.
Related Links
Software for Delphi and C++ Builder developers
Software for Visual Studio .NET developers
Software for Visual Basic 6 developers
Delphi Tips&Tricks
MegaDetailed.NET
TMS Scripter Studio Pro components for Delphi/C++Builder
More Online Helps
Win32 Multimedia Programmer's Reference (mmedia.hlp)
OLE Programmer's Reference (ole.hlp)
Microsoft Windows Pen API Programmer's Reference (penapi.hlp)
Microsoft Windows Sockets 2 Reference (sock2.hlp)
Microsoft Windows Telephony API (TAPI) Programmer's Reference (tapi.hlp)
Unix Manual Pages
|