VB.Net playing mp3 at the same time - vb.net

Question

I've been wondering about this, I have tried multiple suggestions I have got from different sites. I have my code here but it's not working.
Private 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
Private Sub Button3_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button3.Click
Dim fileName As String
FileName = Chr(34) & (Button1.Text) & Chr(34)
mciSendString("open " & FileName & " alias myDevice", Nothing, 0, 0)
mciSendString("play myDevice", Nothing, 0, 0)
FileName = Chr(34) & (Button2.Text) & Chr(34)
mciSendString("open " & FileName & " alias myDevice", Nothing, 0, 0)
mciSendString("play myDevice", Nothing, 0, 0)
This code only plays the first song and will not play the second one...I'm thinking of creating another function similar to the one above with different name but still no luck.
Private Declare Function mciSendString2 Lib "winmm.dll" Alias "mciSendStringA" _
(ByVal lpstrCommand As String, ByVal lpstrReturnString As String, ByVal _
uReturnLength As Integer, ByVal hwndCallback As Integer) As Integer
Any idea? Or is it possible to play multiple mp3 at the same time?

Answer 1

Although I am dealing with a different issue myself, I came across this in my search and can tell you the reason it cannot play the 2 files at the same time is because your alias is the same for both.

Answer 2

This method has worked well for me only during development but most computers I installed on would crash when i would issue the open command via mcisendstring. I haven't figured out why. Here's my code. Maybe it will help someone and maybe someone can figure out what I'm doing wrong. I've had problems getting 32 bit apps to run from my 64 bit development machine.
Imports System.Runtime.InteropServices
Imports System.Text
Public Class MediaPlayerClass
<DllImport("winmm.dll")> _
Private Shared Function mciSendString(ByVal command As String, ByVal buffer As StringBuilder, ByVal bufferSize As Integer, ByVal hwndCallback As IntPtr) As Integer
End Function
<DllImport("winmm.dll")> _
Private Shared Function mciGetErrorString(errCode As Integer, ByVal errMsg As StringBuilder, bufferSize As Integer) As Integer
End Function
<DllImport("kernel32.dll", SetLastError:=True, CharSet:=CharSet.Auto)> _
Public Shared Function GetShortPathName(ByVal longPath As String, _
<MarshalAs(UnmanagedType.LPTStr)> ByVal ShortPath As System.Text.StringBuilder, _
<MarshalAs(Runtime.InteropServices.UnmanagedType.U4)> ByVal bufferSize As Integer) As Integer
End Function
Private _filename As String
Private _MediaAlias As String
Private _Length As TimeSpan
Private _err As Integer
Public Property PlaylistId As Integer = 0
Private _OriginalVolume As Integer = 1000
Function ShortPathName(ByVal Path As String) As String
Dim sb As New System.Text.StringBuilder(1024)
Dim tempVal As Integer = GetShortPathName(Path, sb, 1024)
If tempVal <> 0 Then
Dim Result As String = sb.ToString()
Return Result
Else
Throw New Exception("Failed to return a short path")
End If
End Function
Public Sub New(Filename As String, MediaAlias As String)
_filename = ShortPathName(Filename)
_MediaAlias = MediaAlias.Replace(" ", "_")
'_Length = GetLength()
Try
My.Application.Log.WriteEntry("MediaPlayerClass.New - calling MCI OPEN")
' here is where it crashes
_err = mciSendString("open """ & _filename & """ alias " & MediaAlias, Nothing, 0, 0)
Catch ex As Exception
MsgBox(ex.ToString & vbCrLf & GetLastErrorMessage())
End Try
End Sub
Public Sub NewMP3(Filename As String)
Me.StopIt()
Me.CloseIt()
_filename = Filename
Try
My.Application.Log.WriteEntry("MediaPlayerClass.NewMP3 - calling MCI OPEN ")
_err = mciSendString("open """ & Filename & """ alias " & _MediaAlias, Nothing, 0, 0)
Catch ex As Exception
MsgBox(ex.ToString & vbCrLf & GetLastErrorMessage())
End Try
End Sub
Public ReadOnly Property Length As TimeSpan
Get
Return _length
End Get
End Property
Private Function GetLength() As TimeSpan
Dim lengthBuf As New StringBuilder(32)
Try
My.Application.Log.WriteEntry("MediaPlayerClass.GetLength - calling MCI OPEN")
_err = mciSendString("open """ & _filename & """ type waveaudio alias " & _MediaAlias, Nothing, 0, 0)
Catch ex As Exception
MsgBox(ex.ToString & vbCrLf & GetLastErrorMessage())
End Try
' Get the duration of the music
Try
_err = mciSendString("status wave length", lengthBuf, lengthBuf.Capacity, 0)
Catch ex As Exception
MsgBox(ex.ToString & vbCrLf & GetLastErrorMessage())
End Try
'mciSendString("close wave", Nothing, 0, 0)
Dim len As Integer = Integer.TryParse(lengthBuf.ToString, len)
Dim ts As TimeSpan = TimeSpan.FromMilliseconds(len)
Return ts
End Function
Public Function PlayIt(Optional WaitUntilFinishedPlaying As Boolean = False) As Integer
Try
My.Application.Log.WriteEntry("MediaPlayerClass.PlayIt - calling MCI PLAY")
_err = mciSendString("play " & _MediaAlias, Nothing, 0, IntPtr.Zero)
Catch ex As Exception
MsgBox(ex.ToString)
End Try
While WaitUntilFinishedPlaying
If IsPlaying() Then
Threading.Thread.Sleep(250)
Else
Exit While
End If
End While
Return _err
End Function
Public Function PauseIt() As Integer
_err = mciSendString("pause " & _MediaAlias, Nothing, 0, IntPtr.Zero)
Return _err
End Function
Public Function ResumeIt() As Integer
_err = mciSendString("resume " & _MediaAlias, Nothing, 0, IntPtr.Zero)
Return _err
End Function
Public Function StopIt() As Boolean
_err = mciSendString("stop " & _MediaAlias, Nothing, 0, IntPtr.Zero)
Return _err
End Function
Public Function CloseIt() As Boolean
_err = mciSendString("close " & _MediaAlias, Nothing, 0, IntPtr.Zero)
Return _err
End Function
Public Function IsPlaying() As Boolean
Dim returnData As New StringBuilder(128)
_err = mciSendString("status " & _MediaAlias & " mode", returnData, 128, IntPtr.Zero)
Return (returnData.Length = 7 AndAlso returnData.ToString.Substring(0, 7) = "playing")
End Function
Public Function SetVolume(vol As Integer) As Integer
_err = -1
If vol >= 0 And vol <= 1000 Then
_err = mciSendString("setaudio " & _MediaAlias & " volume to " & vol.ToString, Nothing, 0, IntPtr.Zero)
End If
Return _err
End Function
Public Sub FadeOutAndPause()
_OriginalVolume = GetVolume()
For x As Integer = 30 To 1 Step -1
Me.SetVolume(Int(x / 30 * _OriginalVolume))
Threading.Thread.Sleep(100)
Next
Me.PauseIt()
End Sub
Public Sub PlayAndFadeIn()
Me.PlayIt()
For x As Integer = 1 To 30 Step 1
Me.SetVolume(Int(x / 30 * _OriginalVolume))
Threading.Thread.Sleep(100)
Next
End Sub
Public Function GetVolume() As Integer
Dim returnData As New StringBuilder(128)
_err = mciSendString("status " & _MediaAlias & " volume", returnData, 128, IntPtr.Zero)
'MsgBox(returnData.ToString)
If _err = 0 Then
Return CInt(returnData.ToString)
Else
Return 1000
End If
End Function
Public Function SetBalance(bal As Integer) As Integer
If bal >= 0 AndAlso bal <= 1000 Then
_err = mciSendString("setaudio " & _MediaAlias & " left volume to " + (1000 - bal).ToString, Nothing, 0, IntPtr.Zero)
_err = mciSendString("setaudio " & _MediaAlias & " right volume to " + bal.ToString, Nothing, 0, IntPtr.Zero)
End If
Return _err
End Function
Public Function GetLastErrorMessage() As String
Dim returnData As New StringBuilder(128)
_err = mciGetErrorString(_err, returnData, 128)
Return returnData.ToString.Trim
End Function
Protected Overrides Sub Finalize()
MyBase.Finalize()
CloseIt()
End Sub
End Class