Playing a wav file through MCI

Thread View: comp.lang.basic.visual.misc

3 messages

[T] Back to Threads [V] Tree View [G] Group Articles

3 total messages Started by Curious Student Sat, 19 Jun 2004 13:37

#273

Author: Curious Student
Date: Sat, 19 Jun 2004 13:37

72 lines
3316 bytes

I get an error while playing a wav file. I am using VB6 and the MCI
(winmm.dll) interface. But the front end doesn't matter. I need help
resolving an error that MCI throws back on me when I open the device.
The error comes as a return value to the "Open" string message.

[CODE]
Private Sub Form_Load()
    BoolRecordingOn = False
    If waveOutGetNumDevs() <= 0 Then MsgBox "Your system can't play
sounds.", vbCritical, "Sound Card Not Available"
End Sub

Private Sub cmdOpen_Click()
    c.CancelError = False
    c.ShowOpen
    StrFile = vbNullString
    If Trim(c.FileName) <> vbNullString Then StrFile =
GetShortFileName(c.FileName)
End Sub

Private Sub cmdPlay_Click()

    If StrFile = vbNullString Then Exit Sub
    BoolRecordingOn = False
    cmdRecord.Enabled = False
    
    StrCommand = "Open " & StrFile & " type waveaudio alias StrFile1"
    LngRetVal = mciSendString(StrCommand, vbNullString, 0&, 0&)
    If LngRetVal <> 0 Then DisplayError (LngRetVal)
    
    StrCommand = "Play StrFile1"
    LngRetVal = mciSendString(StrCommand, 0, 0, 0)
    If LngRetVal <> 0 Then DisplayError (LngRetVal)
End Sub

Private Sub DisplayError(ByVal errcode As Long)

Dim errstr As String
Dim retval As Long

errstr = Space(255)
retval = mciGetErrorString(errcode, errstr, Len(errstr))
errstr = Left(errstr, InStr(errstr, vbNullChar) - 1)
retval = MsgBox(errstr, vbOKOnly Or vbCritical)

End Sub

Public Function GetShortFileName(ByVal FileName As String) As String

Dim StrShortFileName As String
Dim LngRetVal As Long

GetShortFileName = vbNullString
StrShortFileName = Space(255)
LngRetVal = GetShortPathName(FileName, StrShortFileName,
Len(StrShortFileName))
Debug.Assert LngRetVal <> 0
StrShortFileName = Left(StrShortFileName, LngRetVal)
GetShortFileName = Trim(StrShortFileName)

End Function
[/CODE]

I get this error message:

[QUOTE][B]No wave device that can play files in the current format is
installed.  Use the Add/Remove Hardware Wizard in Control Panel to
install the wave device.[/B][/QUOTE]

If I didn't the device to support the WAV file, how is it that other
programs like WinAmp can play the same WAV file. Surely I have the
necessary stuff on my system. What do I do?

Re: Playing a wav file through MCI

#274

Author: Gale Green
Date: Sat, 19 Jun 2004 14:40

60 lines
3006 bytes

On 19 Jun 2004 06:37:40 -0700, estudiantin@rediffmail.com (Curious
Student) wrote:

> I get an error while playing a wav file. I am using VB6 and the MCI
> (winmm.dll) interface. But the front end doesn't matter. I need help
> resolving an error that MCI throws back on me when I open the device.
> The error comes as a return value to the "Open" string message.

I copied all your code into a new project, added declarations for all
the variables, and it worked first time.

I believe you may be missing a link in SYSTEM.INI:

waveaudio=mciwave.drv

in group [mci]

You don't say which version of Windows you're using but I believe the
code below will work on all versions because on NT clones
WritePrivateProfileString maps accesses to system INI files to the
registry automatically.

However, if you have Win 95/98/Me, and this project is just for your
own use, then you can edit SYSTEM.INI manually, to include the above
line.

Gale.
===============
Private Declare Function GetWindowsDirectory _
    Lib "kernel32" _
    Alias "GetWindowsDirectoryA" ( _
        ByVal lpBuffer As String, _
        ByVal nSize As Long) As Long

Private Declare Function WritePrivateProfileString _
    Lib "kernel32" _
    Alias "WritePrivateProfileStringA" ( _
        ByVal lpApplicationName As String, _
        ByVal lpKeyName As Any, _
        ByVal lpString As Any, _
        ByVal lpFileName As String) As Long

Dim MyLen  As Long, _
    Temp   As String * 255, _
    WinDir As String, _
    DeviceType As String, _
    DriverName As String

DeviceType = "waveaudio"
DriverName = "mciwave.drv"

MyLen = GetWindowsDirectory(Temp, 255)

WinDir = Left$(Temp, MyLen)

MyLen = WritePrivateProfileString( _
                        "MCI", _
                        DeviceType, _
                        DriverName, _
                        WinDir & "\system.ini")

Re: Playing a wav file through MCI

#275

Author: Gale Green
Date: Sat, 19 Jun 2004 14:48

11 lines
1260 bytes

I forgot... it's also worth checking that the other link is in place,
in WIN.INI.

There should be a line

wav=waveaudio

in group [mci extensions]

Gale.

Thread Navigation

This is a paginated view of messages in the thread with full content displayed inline.

Messages are displayed in chronological order, with the original post highlighted in green.

Use pagination controls to navigate through all messages in large threads.

Back to All Threads