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MCI_PLAY

  • Artikel

The MCI_PLAY command signals the device to begin transmitting output data. CD audio, digital-video, MIDI sequencer, videodisc, VCR, and waveform-audio devices recognize this command.

To send this command, call the mciSendCommand function with the following parameters.

MCIERROR mciSendCommand(
  MCIDEVICEID wDeviceID, 
  MCI_PLAY, 
  DWORD dwFlags, 
  (DWORD) (LPMCI_PLAY_PARMS ) lpPlay
);

Parameters

wDeviceID

Device identifier of the MCI device that is to receive the command message.

dwFlags

MCI_NOTIFY, MCI_WAIT, or, for digital-video and VCR devices, MCI_TEST. For information about these flags, see The Wait, Notify, and Test Flags.

lpPlay

Pointer to an MCI_PLAY_PARMS structure. (Devices with extended command sets might replace this structure with a device-specific structure.)

Return Values

Returns zero if successful or an error otherwise.

Remarks

The following additional flags apply to all devices supporting MCI_PLAY:

MCI_FROM

A starting location is included in the dwFrom member of the structure identified by lpPlay. The units assigned to the position values are specified with the MCI_SET_TIME_FORMAT flag of the MCI_SET command. If MCI_FROM is not specified, the starting location defaults to the current position.

MCI_TO

An ending location is included in the dwTo member of the structure identified by lpPlay. The units assigned to the position values are specified with the MCI_SET_TIME_FORMAT flag of MCI_SET. If MCI_TO is not specified, the ending location defaults to the end of the media.

The following additional flags are used with the digitalvideo device type:

MCI_DGV_PLAY_REPEAT

Playback should start again at the beginning when the end of the content is reached.

MCI_DGV_PLAY_REVERSE

Playback should occur in reverse.

MCI_MCIAVI_PLAY_WINDOW

Playback should occur in the window associated with a device instance (the default). (This flag is specific to MCIAVI.DRV.)

MCI_MCIAVI_PLAY_FULLSCREEN

Playback should use a full-screen display. Use this flag only when playing compressed or 8-bit files.

For digital-video devices, lpPlay points to an MCI_DGV_PLAY_PARMS structure.

The following additional flags are used with the vcr device type:

MCI_VCR_PLAY_AT

The dwAt member of the structure identified by lpPlay contains a time when the entire command begins, or if the device is cued, when the device reaches the from position given by the MCI_CUE command.

MCI_VCR_PLAY_REVERSE

Playback should occur in reverse.

MCI_VCR_PLAY_SCAN

Playback should be as fast as possible while maintaining video output.

For VCR devices, lpPlay points to an MCI_VCR_PLAY_PARMS structure.

The following additional flags are used with the videodisc device type:

MCI_VD_PLAY_FAST

Play fast.

MCI_VD_PLAY_REVERSE

Play in reverse.

MCI_VD_PLAY_SCAN

Scan quickly.

MCI_VD_PLAY_SLOW

Play slowly.

MCI_VD_PLAY_SPEED

The play speed is included in the dwSpeed member in the structure identified by lpPlay.

Requirements

**  Windows NT/2000/XP:** Included in Windows NT 3.1 and later.
**  Windows 95/98/Me:** Included in Windows 95 and later.
**  Header:** Declared in Mmsystem.h; include Windows.h.

See Also

MCI, MCI Commands, MCI_CUE, MCI_DGV_PLAY_PARMS, MCI_PLAY_PARMS, MCI_SET, MCI_VCR_PLAY_PARMS, MCI_VD_PLAY_PARMS