Is there a way to grab the send key on Windows Mobile and dial its specific number?

I can confirm that using SHCMBM_OVERRIDEKEY works on both PPC and SP devices. I tested it on WM5 PPC, WM5 SP, WM6 PPC, WM6 SP. I haven't tried WM6.1 or WM6.5 yet, but I kind of assume they have been working since WM6 has worked.

Also, you might need DTMF support during a call?

Since I was writing the LAP-dll, I followed the following page that you might find helpful: Problems with LAP Execution

These examples are in C, so you'll have to translate them to C #.

To customize the capture of the talk key for a specific window, you need to do:

SendMessage(SHFindMenuBar(window_hwnd), 
            SHCMBM_OVERRIDEKEY, 
            VK_TTALK, 
            MAKELPARAM((SHMBOF_NODEFAULT|SHMBOF_NOTIFY), (SHMBOF_NODEFAULT|SHMBOF_NOTIFY));

      

        
        
        
      

    

You can turn on / off the trap at any time. It's also easy to disable the trap:

SendMessage(SHFindMenuBar(window_hwnd), 
            SHCMBM_OVERRIDEKEY, 
            VK_TTALK, 
            MAKELPARAM(0, (SHMBOF_NODEFAULT|SHMBOF_NOTIFY));

      

        
        
        
      

    

To detect when the Talk key is pressed, you need to lure the WM_HOTKEY message box window into the proc window:

case WM_HOTKEY:
    switch(HIWORD(lParam))
    {
    case VK_TTALK:
        // make ph call
        break;
    }
    return TRUE;

      

        
        
        
      

    

To make a phone call, you need to use the "PhoneMakeCall" API:

#include <phone.h>

void MakePhoneCall(const wchar_t* number)
{
    PHONEMAKECALLINFO call;
    memset(&call, 0x0, sizeof(PHONEMAKECALLINFO));
    call.cbSize = sizeof(PHONEMAKECALLINFO);
    call.dwFlags = PMCF_DEFAULT;
    call.pszDestAddress = number;
    PhoneMakeCall(&call);
}

      

        
        
        
      

    

For DTMF support during a phone call, you need to track the phone call using SNAPI (I believe there is a C # library to help you with SystemProperty there ).

Setting after starting a call:

  #include <snapi.h>
  RegistryNotifyWindow(SN_PHONEACTIVECALLCOUNT_ROOT, SN_PHONEACTIVECALLCOUNT_PATH, SN_PHONEACTIVECALLCOUNT_VALUE, window_hwnd, callback_window_msg_number /*e.g. WM_APP */, 0, NULL, &phone_call_notify_handle);

      

        
        
        
      

    

You will be returned with a window message that you provide when changing the number of calls. You need to read the registry and check that the call count drops to zero. If you need to close the SNAPI handle:

RegistryCloseNotification(phone_call_notify_handle);

      

        
        
        
      

    

During the call, send a message to the cprog application using the key that was pressed by the user:

#define WM_CPROG_SEND_VKEY_DTMF (WM_APP+3) // Sends the DTMF tone(s) through to the current call (converting from VKEY to DTMF chars)

  BOOL PhoneSendDTMF(UINT uvKey)
  {
    BOOL bRet = FALSE;
    static HWND s_hwndCProg = NULL;
    TCHAR chDTMF = MapVKeyToChar(uvKey);

    // Attempt to find the cprog window (MSCprog).
    // Try to keep this window handle cached.
    if(NULL == s_hwndCProg || !IsWindow(s_hwndCProg))
    {
      s_hwndCProg = FindWindow(TEXT("MSCprog"), NULL);
    }

    // Send WM_CPROG_SEND_VKEY_DTMF to the CProg window.
    if(NULL != s_hwndCProg)
    {
      bRet = BOOLIFY(PostMessage(s_hwndCProg,
                              WM_CPROG_SEND_VKEY_DTMF, (WPARAM)chDTMF, 0));
    }

    return bRet;
  }