topic Re: Listen for escape pressed in .NET Forum

Listen for escape pressed

Anonymous — Fri, 04 Jan 2013 10:57:53 GMT

Is there a way to add a listener so I am told when escape(cancel command) is pressed? I want to create a cancel pressed event.

Re: Listen for escape pressed

Alexander.Rivilis — Fri, 04 Jan 2013 16:25:10 GMT

This way can help you:

How to implement a Windows Hook using acedRegisterFilterWinMsg in .NET

In WindowHookProc event handler you can check msg.Msg == WM_KEYDOWN (0x0100) and msg.WParam == VK_ESCAPE (0x1B)

Re: Listen for escape pressed

Anonymous — Mon, 07 Jan 2013 08:58:11 GMT

Thanks, that seems to work, but how do you unregister the listener? When escape is pressed I want to do something and then unregister the listener.

Re: Listen for escape pressed

Alexander.Rivilis — Mon, 07 Jan 2013 10:36:14 GMT

In order to unregister this event handler use function acedRemoveFilterWinMsg:

BOOL acedRemoveFilterWinMsg(
    const AcedFilterWinMsgFn pfn
);

In C# it is look like:

// For AutoCAD 2013 64 bit
// On previous versions, import from acad.exe (instead accore.dll)
[DllImport("accore.dll",  CharSet = CharSet.Unicode, CallingConvention = CallingConvention.Cdecl, EntryPoint = "?acedRemoveFilterWinMsg@@YAHQ6AHPEAUtagMSG@@@Z@Z")]
private static extern int acedRemoveFilterWinMsg( WindowHookProc callBackFunc );

Re: Listen for escape pressed

Anonymous — Mon, 07 Jan 2013 11:11:51 GMT

Thank you very much.