I have a school bell project coded with Visual Basic 2010 Express. The computer which runs my program has two or more sound cards. First I will list the sound cards to user. User will select the sound card to work. Finally my program will ring the bells on that sound card. Everything is okey for my codes but i can't list the names of sound cards and ring the bell on specified sound card.
I use WMPLib to play music. I have these codes but there becomes an error "the value is not in the expected range". I spotted where the error is in my codes:
Public Declare Function waveOutGetNumDevs Lib "winmm" () As Integer
Public Declare Function mciSendCommand Lib "winmm.dll" Alias "mciSendCommandA" (ByVal wDeviceID As Integer, ByVal uMessage As String, ByVal dwParam1 As Integer, ByVal dwParam2 As Object) As Integer
Public Declare Function mciGetErrorString Lib "winmm.dll" Alias "mciGetErrorStringA" (ByVal dwError As Integer, ByVal lpstrBuffer As String, ByVal uLength As Integer) As Integer
Public Declare Function mciSendString Lib "winmm.dll" Alias "mciSendStringA" (ByVal lpstrCommand As String, ByVal lpstrReturnString As String, ByVal uReturnLength As Integer, ByVal hwndCallback As Integer) As Integer
Public Declare Function mciGetDeviceID Lib "winmm.dll" Alias "mciGetDeviceIDA" (ByVal lpstrName As String) As Integer
Public Const MMSYSERR_NOERROR = 0
Public Const MCI_SET = &H80D
Public Const MCI_WAVE_OUTPUT = &H800000
Public Structure MCI_WAVE_SET_PARMS
Dim dwCallback As Integer
Dim dwTimeFormat As Integer
Dim dwAudio As Integer
Dim wInput As Integer
Dim wOutput As Integer
Dim wFormatTag As Short
Dim wReserved2 As Short
Dim nChannels As Short
Dim wReserved3 As Short
Dim nSamplesPerSec As Integer
Dim nAvgBytesPerSec As Integer
Dim nBlockAlign As Short
Dim wReserved4 As Short
Dim wBitsPerSample As Short
Dim wReserved5 As Short
End Structure
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
Dim parms As MCI_WAVE_SET_PARMS
Dim wDeviceID As Integer
Dim ret As Integer
parms.wOutput = 0
wDeviceID = mciGetDeviceID("waveaudio")
' the value is not in the expected range error is here and it spots parms
ret = mciSendCommand(wDeviceID, MCI_SET, MCI_WAVE_OUTPUT, parms)
If (ret <> MMSYSERR_NOERROR) Then
Stop
End If
If ofd.ShowDialog Then
ret = mciSendString("Open " & Chr(34) & ofd.FileName & Chr(34) & " alias audio", CStr(0), 0, 0)
ret = mciSendString("Open audio", CStr(0), 0, 0)
End If
End Sub
You can do this using WindowsMedia.Net library.
The following example is taken from the link below, it is a code blonging to a Windows form and contains the functionality needed to list all available audio devices and choose the default device (the one that will act as sound output).
First i will try to split the code into 2 parts:
List available devices
Private Sub RefreshInformation()
PopulateDeviceComboBox()
DisplayDefaultWaveOutDevice()
End Sub
Private Sub PopulateDeviceComboBox()
DevicesComboBox.Items.Clear()
' How many wave out devices are there? WaveOutGetNumDevs API call.
Dim waveOutDeviceCount As Integer = waveOut.GetNumDevs()
For i As Integer = 0 To waveOutDeviceCount - 1
Dim caps As New WaveOutCaps
' Get a name - its in a WAVEOUTCAPS structure.
' The name is truncated to 31 chars by the api call. You probably have to
' dig around in the registry to get the full name.
Dim result As Integer = waveOut.GetDevCaps(i, caps, Marshal.SizeOf(caps))
If result <> MMSYSERR.NoError Then
Dim err As MMSYSERR = DirectCast(result, MMSYSERR)
Throw New Win32Exception("GetDevCaps() error, Result: " & result.ToString("x8") & ", " & err.ToString)
End If
DevicesComboBox.Items.Add(New WaveOutDevice(i, caps))
Next
DevicesComboBox.SelectedIndex = 0
End Sub
Private Sub DisplayDefaultWaveOutDevice()
Dim currentDefault As Integer = GetIdOfDefaultWaveOutDevice()
Dim device As WaveOutDevice = DirectCast(DevicesComboBox.Items(currentDefault), WaveOutDevice)
DefaultDeviceLabel.Text = "Defualt: " & device.WaveOutCaps.szPname
End Sub
Private Function GetIdOfDefaultWaveOutDevice() As Integer
Dim id As Integer = 0
Dim hId As IntPtr
Dim flags As Integer = 0
Dim hFlags As IntPtr
Dim result As Integer
Try
' It would be easier to declare a nice overload with ByRef Integers.
hId = Marshal.AllocHGlobal(4)
hFlags = Marshal.AllocHGlobal(4)
' http://msdn.microsoft.com/en-us/library/bb981557.aspx
result = waveOut.Message(WAVE_MAPPER, DRVM_MAPPER_PREFERRED_GET, hId, hFlags)
If result <> MMSYSERR.NoError Then
Dim err As MMSYSERR = DirectCast(result, MMSYSERR)
Throw New Win32Exception("waveOutMessage() error, Result: " & result.ToString("x8") & ", " & err.ToString)
End If
id = Marshal.ReadInt32(hId)
flags = Marshal.ReadInt32(hFlags)
Finally
Marshal.FreeHGlobal(hId)
Marshal.FreeHGlobal(hFlags)
End Try
' There is only one flag, DRVM_MAPPER_PREFERRED_FLAGS_PREFERREDONLY, defined as 1
' "When the DRVM_MAPPER_PREFERRED_FLAGS_PREFERREDONLY flag bit is set, ... blah ...,
' the waveIn and waveOut APIs use only the current preferred device and do not search
' for other available devices if the preferred device is unavailable.
Return id
End Function
Change default device
Private Sub SetDefaultButton_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles SetDefaultButton.Click
If DevicesComboBox.Items.Count = 0 Then Return
Dim selectedDevice As WaveOutDevice = DirectCast(DevicesComboBox.SelectedItem, WaveOutDevice)
SetDefault(selectedDevice.Id)
RefreshInformation()
End Sub
Private Sub SetDefault(ByVal id As Integer)
Dim defaultId As Integer = GetIdOfDefaultWaveOutDevice()
If defaultId = id Then Return ' no change.
Dim result As Integer
' So here we say "change the Id of the device that has id id to 0", which makes it the default.
result = waveOut.Message(WAVE_MAPPER, DRVM_MAPPER_PREFERRED_SET, New IntPtr(id), IntPtr.Zero)
If result <> MMSYSERR.NoError Then
Dim err As MMSYSERR = DirectCast(result, MMSYSERR)
Throw New Win32Exception("waveOutMessage() error, Result: " & result.ToString("x8") & ", " & err.ToString)
End If
End Sub
Full code
Imports MultiMedia
Imports System.Runtime.InteropServices
Imports System.ComponentModel
Public Class Form1
Private DevicesComboBox As New ComboBox
Private DefaultDeviceLabel As New Label
Private WithEvents SetDefaultButton As New Button
Private Const DRVM_MAPPER_PREFERRED_GET As Integer = &H2015
Private Const DRVM_MAPPER_PREFERRED_SET As Integer = &H2016
Private WAVE_MAPPER As New IntPtr(-1)
' This just brings together a device ID and a WaveOutCaps so
' that we can store them in a combobox.
Private Structure WaveOutDevice
Private m_id As Integer
Public Property Id() As Integer
Get
Return m_id
End Get
Set(ByVal value As Integer)
m_id = value
End Set
End Property
Private m_caps As WaveOutCaps
Public Property WaveOutCaps() As WaveOutCaps
Get
Return m_caps
End Get
Set(ByVal value As WaveOutCaps)
m_caps = value
End Set
End Property
Sub New(ByVal id As Integer, ByVal caps As WaveOutCaps)
m_id = id
m_caps = caps
End Sub
Public Overrides Function ToString() As String
Return WaveOutCaps.szPname
End Function
End Structure
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
' I do use the IDE for this stuff normally... (in case anyone is wondering)
Me.Controls.AddRange(New Control() {DevicesComboBox, DefaultDeviceLabel, SetDefaultButton})
DevicesComboBox.Location = New Point(5, 5)
DevicesComboBox.DropDownStyle = ComboBoxStyle.DropDownList
DevicesComboBox.Width = Me.ClientSize.Width - 10
DevicesComboBox.Anchor = AnchorStyles.Left Or AnchorStyles.Right
DefaultDeviceLabel.Location = New Point(DevicesComboBox.Left, DevicesComboBox.Bottom + 5)
DefaultDeviceLabel.AutoSize = True
SetDefaultButton.Location = New Point(DefaultDeviceLabel.Left, DefaultDeviceLabel.Bottom + 5)
SetDefaultButton.Text = "Set Default"
SetDefaultButton.AutoSize = True
RefreshInformation()
End Sub
Private Sub RefreshInformation()
PopulateDeviceComboBox()
DisplayDefaultWaveOutDevice()
End Sub
Private Sub PopulateDeviceComboBox()
DevicesComboBox.Items.Clear()
' How many wave out devices are there? WaveOutGetNumDevs API call.
Dim waveOutDeviceCount As Integer = waveOut.GetNumDevs()
For i As Integer = 0 To waveOutDeviceCount - 1
Dim caps As New WaveOutCaps
' Get a name - its in a WAVEOUTCAPS structure.
' The name is truncated to 31 chars by the api call. You probably have to
' dig around in the registry to get the full name.
Dim result As Integer = waveOut.GetDevCaps(i, caps, Marshal.SizeOf(caps))
If result <> MMSYSERR.NoError Then
Dim err As MMSYSERR = DirectCast(result, MMSYSERR)
Throw New Win32Exception("GetDevCaps() error, Result: " & result.ToString("x8") & ", " & err.ToString)
End If
DevicesComboBox.Items.Add(New WaveOutDevice(i, caps))
Next
DevicesComboBox.SelectedIndex = 0
End Sub
Private Sub DisplayDefaultWaveOutDevice()
Dim currentDefault As Integer = GetIdOfDefaultWaveOutDevice()
Dim device As WaveOutDevice = DirectCast(DevicesComboBox.Items(currentDefault), WaveOutDevice)
DefaultDeviceLabel.Text = "Defualt: " & device.WaveOutCaps.szPname
End Sub
Private Function GetIdOfDefaultWaveOutDevice() As Integer
Dim id As Integer = 0
Dim hId As IntPtr
Dim flags As Integer = 0
Dim hFlags As IntPtr
Dim result As Integer
Try
' It would be easier to declare a nice overload with ByRef Integers.
hId = Marshal.AllocHGlobal(4)
hFlags = Marshal.AllocHGlobal(4)
' http://msdn.microsoft.com/en-us/library/bb981557.aspx
result = waveOut.Message(WAVE_MAPPER, DRVM_MAPPER_PREFERRED_GET, hId, hFlags)
If result <> MMSYSERR.NoError Then
Dim err As MMSYSERR = DirectCast(result, MMSYSERR)
Throw New Win32Exception("waveOutMessage() error, Result: " & result.ToString("x8") & ", " & err.ToString)
End If
id = Marshal.ReadInt32(hId)
flags = Marshal.ReadInt32(hFlags)
Finally
Marshal.FreeHGlobal(hId)
Marshal.FreeHGlobal(hFlags)
End Try
' There is only one flag, DRVM_MAPPER_PREFERRED_FLAGS_PREFERREDONLY, defined as 1
' "When the DRVM_MAPPER_PREFERRED_FLAGS_PREFERREDONLY flag bit is set, ... blah ...,
' the waveIn and waveOut APIs use only the current preferred device and do not search
' for other available devices if the preferred device is unavailable.
Return id
End Function
Private Sub SetDefaultButton_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles SetDefaultButton.Click
If DevicesComboBox.Items.Count = 0 Then Return
Dim selectedDevice As WaveOutDevice = DirectCast(DevicesComboBox.SelectedItem, WaveOutDevice)
SetDefault(selectedDevice.Id)
RefreshInformation()
End Sub
Private Sub SetDefault(ByVal id As Integer)
Dim defaultId As Integer = GetIdOfDefaultWaveOutDevice()
If defaultId = id Then Return ' no change.
Dim result As Integer
' So here we say "change the Id of the device that has id id to 0", which makes it the default.
result = waveOut.Message(WAVE_MAPPER, DRVM_MAPPER_PREFERRED_SET, New IntPtr(id), IntPtr.Zero)
If result <> MMSYSERR.NoError Then
Dim err As MMSYSERR = DirectCast(result, MMSYSERR)
Throw New Win32Exception("waveOutMessage() error, Result: " & result.ToString("x8") & ", " & err.ToString)
End If
End Sub
End Class
You can retrieve the available audio devices using System.Management assembly which is a part of .Net framework:
ManagementObjectSearcher mo =
new ManagementObjectSearcher("select * from Win32_SoundDevice");
foreach (ManagementObject soundDevice in mo.Get())
{
String deviceId = soundDevice.GetPropertyValue("DeviceId").ToString();
String name = soundDevice.GetPropertyValue("Name").ToString();
//saving the name and device id in array
}
References