PhoneSendDTMFStart

4/8/2010

This function allows an application to begin sending a Dual-Tone Multi-frequency (DTMF) tone using the current phone call.

Syntax

HRESULT PhoneSendDTMFStart (
  TCHAR chDTMF
);

Parameters

• chDTMF
  [in] Desired DTMF character to send. Must be '0'-'9', 'A'-'D', '*', or '#'.

Return Value

Value	Description
S_OK	The operation completed successfully.
E_FAIL	An unknown error occurred.
E_INVALIDARG	chDTMF is invalid.
E_NOTIMPL	No phone is present on the device, the phone service is not running, or no calls are currently active.

Remarks

Caller must call PhoneSendDTMFStop to stop the DTMF tone.

This function will fail if no phone is present on the device, the phone service is not running, or no calls are currently active. If a subsequent call to this API is made by the caller or any other application before the DTMF tone is finished the original DTMF tone will cease and the new DTMF will be sent.

Note

Currently DTMFs are always intoned for the default duration, regardless of when PhoneSendDTMFStop is called.

Requirements

Header	phone.h
Library	phone.lib
Windows Mobile	Windows Mobile 6 Classic and later, Windows Mobile 6 Professional and later, Windows Mobile 6 Standard and later