[VisualBasic]2 Fragen bzgl. Buttons & Listbox

'------------ Anfang Projektdatei trMP3info.vbp ------------
'--- Anfang Klasse "HeaderInfos" alias clsHeaderInfos.cls ---


'------------ Anfang Projektdatei trMP3info.vbp ------------
'--- Anfang Klasse "HeaderInfos" alias clsHeaderInfos.cls ---
Option Explicit

Private anBitrateLookup(7, 15) As Integer
Private alFreqLookup(3, 7) As Long
Private avFrameRates(3)

'#####################################################################

Private m_sFilePath As String
Private m_lFileSize As Long
Private m_bytVersion As Byte
Private m_bytLayer As Byte
Private m_bCRCProtected As Boolean
Private m_lBitrate As Long
Private m_lFrequency As Long
Private m_bPadding As Boolean
Private m_bPrivateBit As Boolean
Private m_bytChannelMode As Byte
Private m_bytChannelModeExtention As Byte
Private m_bCopyright As Boolean
Private m_bOriginal As Boolean
Private m_bytEmphasis As Byte
Private m_sVersionText As String
Private m_sLayerText As String
Private m_sChannelModeText As String
Private m_sEmphasisText As String
Private m_lFrameSize As Long
Private m_lFrames As Long
Private m_lSeconds As Long
Private m_ID3V2 As Boolean
Private m_ID3V1 As Boolean
Private m_HeaderPosition As Long

'#####################################################################

Public Property Get FilePath() As String
 FilePath = m_sFilePath
End Property

Public Property Let FilePath(sValue As String)
 Call ZeroValues
 m_sFilePath = sValue
End Property

Public Property Get FileSize() As String
 FileSize = m_lFileSize
End Property

Public Property Get Version() As Byte
 Version = m_bytVersion
End Property

Public Property Get Layer() As Byte
 Layer = m_bytLayer
End Property

Public Property Get CRCProtected() As Boolean
 CRCProtected = m_bCRCProtected
End Property

Public Property Get Bitrate() As Long
 Bitrate = m_lBitrate
End Property

Public Property Get Frequency() As Long
 Frequency = m_lFrequency
End Property

Public Property Get Padding() As Boolean
 Padding = m_bPadding
End Property

Public Property Get PrivateBit() As Boolean
 PrivateBit = m_bPrivateBit
End Property

Public Property Get ChannelMode() As Byte
 ChannelMode = m_bytChannelMode
End Property

Public Property Get ChannelModeExtention() As Byte
 ChannelModeExtention = m_bytChannelModeExtention
End Property

Public Property Get Copyright() As Boolean
 Copyright = m_bCopyright
End Property

Public Property Get Original() As Boolean
 Original = m_bOriginal
End Property

Public Property Get Emphasis() As Byte
 Emphasis = m_bytEmphasis
End Property

Public Property Get VersionText() As String
 VersionText = m_sVersionText
End Property

Public Property Get LayerText() As String
 LayerText = m_sLayerText
End Property

Public Property Get ChannelModeText() As String
 ChannelModeText = m_sChannelModeText
End Property

Public Property Get EmphasisText() As String
 EmphasisText = m_sEmphasisText
End Property

Public Property Get FrameSize() As Long
 FrameSize = m_lFrameSize
End Property

Public Property Get Frames() As Long
 Frames = m_lFrames
End Property

Public Property Get Seconds() As Long
 Seconds = m_lSeconds
End Property

Public Property Get HeaderPosition() As Long
 HeaderPosition = m_HeaderPosition
End Property

Public Property Get ID3V1() As Boolean
 ID3V1 = m_ID3V1
End Property

Public Property Get ID3V2() As Boolean
 ID3V2 = m_ID3V2
End Property

'#####################################################################

Private Sub Class_Initialize()
 Dim asBitrateCore() As String, asFreqCore() As String
 Dim sBitrateData As String, sFreqData As String
 Dim nBitRate As Integer, nVerLayer As Integer, nFreq As Integer

 sBitrateData = "999,999,999,999,999,999," & _
 "032,032,032,032,008,008," & _
 "064,048,040,048,016,016," & _
 "096,056,048,056,024,024," & _
 "128,064,056,064,032,032," & _
 "160,080,064,080,040,040," & _
 "192,096,080,096,048,048," & _
 "224,112,096,112,056,056," & _
 "256,128,112,128,064,064," & _
 "288,160,128,144,080,080," & _
 "320,192,160,160,096,096," & _
 "352,224,192,176,112,112," & _
 "384,256,224,192,128,128," & _
 "416,320,256,224,144,144," & _
 "448,384,320,256,160,160," & _
 "999,999,999,999,999,999"

 asBitrateCore = Split(sBitrateData, ",")

 For nBitRate = 1 To 14
 For nVerLayer = 0 To 2
 anBitrateLookup(7 - nVerLayer, nBitRate) = _
 Val(asBitrateCore((nBitRate * 6) + nVerLayer))
 Next
 For nVerLayer = 0 To 2
 anBitrateLookup(3 - nVerLayer, nBitRate) = _
 Val(asBitrateCore((nBitRate * 6) + 3 + nVerLayer))
 Next
 Next

 sFreqData = "44100,22050,11025," & _
 "48000,24000,12000," & _
 "32000,16000,08000," & _
 "99999,99999,99999"

 asFreqCore = Split(sFreqData, ",")

 For nFreq = 0 To 3
 alFreqLookup(3, nFreq) = Val(asFreqCore((nFreq * 3)))
 alFreqLookup(2, nFreq) = Val(asFreqCore((nFreq * 3) + 1))
 alFreqLookup(0, nFreq) = Val(asFreqCore((nFreq * 3) + 2))
 Next

 avFrameRates(0) = 38.5
 avFrameRates(1) = 32.5
 avFrameRates(2) = 27.8
 avFrameRates(3) = 0
End Sub

'#####################################################################

Private Sub ZeroValues()
 m_lFileSize = 0
 m_bytVersion = 0
 m_bytLayer = 0
 m_bCRCProtected = False
 m_lBitrate = 0
 m_lFrequency = 0
 m_bPadding = False
 m_bPrivateBit = False
 m_bytChannelMode = 0
 m_bytChannelModeExtention = 0
 m_bCopyright = False
 m_bOriginal = False
 m_bytEmphasis = 0
 m_sVersionText = ""
 m_sLayerText = ""
 m_sChannelModeText = ""
 m_sEmphasisText = ""
 m_lFrameSize = 0
 m_lFrames = 0
 m_lSeconds = 0
End Sub

Public Function GetFileInfos()
 Dim nFile As Integer
 Dim i As Long, z As Integer
 Dim sInput As String, sMP3bitsString As String
 Dim nBit1 As Integer, nBit2 As Integer
 Dim nBitD1 As Integer, nBitD2 As Integer
 Dim dSHIFT, LayerType, FrameSize
 Dim mp3_ID1, mp3_bitrate, mp3_protection, mp3_frequency
 Dim aBytes(3) As Byte
 Dim ID3V2Len As Long
 Dim sID3Len As String
 Dim ID3Position As Long
 Dim HDPos As Long
 
 m_ID3V2 = False
 GetFileInfos = -1
 If Not FileExists(m_sFilePath) Then Exit Function
 GetFileInfos = 0
 nFile = FreeFile
 Open m_sFilePath For Binary As #nFile
 Seek #nFile, LOF(nFile) - 127
 sInput = Input(128, #nFile)
 If Left(sInput, 3) = "TAG" Then
 m_ID3V1 = True
 End If
 Seek #nFile, 1
 
 'Einlesen der ersten vier Kilobytes um
 'den Header der Datei zu finden
 sInput = Input(8192, #nFile)
 
 'Wird für die Berechnung der Trackduration benötigt
 m_lFileSize = LOF(nFile)
 
 ' Ist ein ID3V2-Tag vorhanden?
 If Left$(sInput, 3) = "ID3" Then
 ID3Position = 1
 m_ID3V2 = True
 End If
 
 If ID3Position Then
 
 ' Bytes mit Längen-Info des Tags lesen
 sID3Len = Mid$(sInput, ID3Position + 6, 4)
 
 ' länge des Tags berechnen
 ID3V2Len = &H200000 * Asc(Left$(sID3Len, 1)) + _
 &H4000 * Asc(Mid$(sID3Len, 2, 1)) + _
 &H80 * Asc(Mid$(sID3Len, 3, 1)) + _
 Asc(Mid$(sID3Len, 4, 1))
 
 ' Tag überspringen
 Seek #nFile, ID3Position + ID3V2Len + 10
 
 'wird benötigt zur Berechnung der Headerposition
 HDPos = ID3Position + ID3V2Len + 10
 m_lFileSize = m_lFileSize - (ID3Position + ID3V2Len + 10)
 
 ' neuen Einlesen
 sInput = Input(8192, #nFile)
 End If
 Close #nFile
 

 i = 0
 Do Until i = 8191
ReEnter:
 i = i + 1
 nBit1 = Asc(Mid(sInput, i, 1))
 nBit2 = Asc(Mid(sInput, i + 1, 1))
 If nBit1 = &HFF And (nBit2 And &HE0) = &HE0 Then
 
 '20 HeadersBits auslesen - es sind die
 'letzen 20 Bits der nexten 3 Bytes
 sMP3bitsString = Mid(sInput, i + 1, 3)
 m_HeaderPosition = HDPos + i - 1
 Exit Do
 End If
 
 'Wir haben die Sync nicht gefunden, deshalb
 'verschieben wir das ganze um 4Bits nach links
 dSHIFT = ShiftBits(Mid(sInput, i, 3))
 nBitD1 = Asc(Left(dSHIFT, 1))
 nBitD2 = Asc(Right(dSHIFT, 1))
 
 If nBitD1 = &HFF And (nBitD2 And &HE0) = &HE0 Then
 '20 HeaderBits auslesen - es sind die
 'ersten 20 Bits der nexten 3 Bytes
 sMP3bitsString = Mid(sInput, i + 2, 3)
 m_HeaderPosition = HDPos + i - 1
 Exit Do
 End If
 Loop

 If i = 8191 Then Exit Function 'Header wurde nicht gefunden!
 ' -> beenden der Routine

 For z = 1 To 3
 aBytes(z) = Asc(Mid(sMP3bitsString, z))
 Next

 'Die ersten 20 Bits von sMP3bitsString sind die
 'Headerinformationen für diesen Frame
 '1te Bit: ID | 0 = MPEG-2 | 1 = MPEG-1
 m_bytVersion = (&H18 And aBytes(1)) / 8
 mp3_ID1 = (m_bytVersion And 1)
 
 'folgende 2 Bits sind der Layer
 m_bytLayer = (&H6 And aBytes(1)) / 2
 
 'folgendes Bit ist Protection
 mp3_protection = &H1 And aBytes(1)
 m_bCRCProtected = mp3_protection <> 0
 
 'folgende 4 Bits sind die Bitrate
 mp3_bitrate = (&HF0 And aBytes(2)) / 16
 LayerType = (mp3_ID1 * 4) Or m_bytLayer
 m_lBitrate = 1000 * CLng((anBitrateLookup(LayerType, mp3_bitrate)))
 
 'folgende 2 Bits sind die Frequenz
 mp3_frequency = (&HC And aBytes(2)) / 4
 m_lFrequency = alFreqLookup(m_bytVersion, mp3_frequency)
 If m_lFrequency = 99999 Or m_lFrequency = 0 Or m_lBitrate = 0 Then
 i = i + 4
 Goto ReEnter
 End If
 
 'folgendes Bit ist das Padding Bit
 m_bPadding = ((&H2 And aBytes(2)) / 2) = 1
 
 'folgendes Bit ist das Private Bit
 m_bPrivateBit = ((&H10 And aBytes(3)) / 2) = 1
 
 'folgende 2 Bit sind der Channel mode
 m_bytChannelMode = (&HC0 And aBytes(3)) / 64
 
 'folgende 2 Bits sind die Channel Mode Extention
 m_bytChannelModeExtention = (&H30 And aBytes(3)) / 16
 
 'folgendes Bit ist der Copyright Flag
 m_bCopyright = ((&H8 And aBytes(3)) / 8) = 1
 
 'folgendes Bit ist das Original Flag
 m_bOriginal = ((&H4 And aBytes(3)) / 4) = 1
 
 'folgendes Bit ist das Emphasis Flag
 m_bytEmphasis = &H3 And aBytes(3)

 Select Case m_bytVersion
 Case 0
 m_sVersionText = "MPEG-2.5"
 Case 1
 Case 2
 m_sVersionText = "MPEG-2.0"
 Case 3
 m_sVersionText = "MPEG-1.0"
 End Select

 Select Case m_bytLayer
 Case 1
 m_sLayerText = "Layer III"
 FrameSize = (144 * (m_lBitrate / m_lFrequency))
 Case 2
 m_sLayerText = "Layer II"
 FrameSize = (144 * (m_lBitrate / m_lFrequency))
 Case 3
 m_sLayerText = "Layer I"
 FrameSize = ((12 * (m_lBitrate / m_lFrequency) + _
 Abs(m_bPadding))) * 4
 End Select

 Select Case m_bytChannelMode
 Case 0
 m_sChannelModeText = "Stereo"
 Case 1
 m_sChannelModeText = "Joint Stereo (Stereo)"
 If m_bytVersion < 3 Then FrameSize = Fix(FrameSize) / 2
 If m_bytVersion = 0 Then FrameSize = Fix(FrameSize) / 2
 Case 2
 m_sChannelModeText = "Dual Channel (Stereo)"
 Case 3
 m_sChannelModeText = "Single Channel (Mono)"
 If m_bytVersion < 3 Then FrameSize = Fix(FrameSize) / 2
 End Select

 Select Case m_bytEmphasis
 Case 0
 m_sEmphasisText = "None"
 Case 1
 m_sEmphasisText = "50/15 ms"
 Case 2
 m_sEmphasisText = "reserved"
 Case 3
 m_sEmphasisText = "CIT J.17"
 End Select

 'Ausrechnen der Frameanzahl und der Spieldauer
 m_lFrameSize = Fix(FrameSize)
 m_lFrames = m_lFileSize / Fix(FrameSize)
 m_lSeconds = m_lFrames / avFrameRates(mp3_frequency)
End Function

Private Function ShiftBits(sInput As String) As String
 Dim nSD1, nSD2, nSD3, nDO1, nDO2 As Integer
 
 nSD1 = Asc(Left(sInput, 1))
 nSD2 = Asc(Mid(sInput, 2, 1))
 nSD3 = Asc(Right(sInput, 1))

 nDO1 = ((nSD1 And &HF) * 16) Or ((nSD2 And &HF0) / 16)
 nDO2 = ((nSD2 And &HF) * 16) Or ((nSD3 And &HF0) / 16)
 ShiftBits = Chr(nDO1) + Chr(nDO2)
End Function

Private Function FileExists(ByVal FileName As String) As Boolean
 On Error Resume Next
 FileExists = (GetAttr(FileName) >= vbNormal)
End Function




'---- Ende Klasse "HeaderInfos" alias clsHeaderInfos.cls ----
'------- Anfang Formular "frmMain" alias frmMain.frm -------
' Steuerelement: Listen-Steuerelement "lstHeaderInfos"
' Steuerelement: Beschriftungsfeld "lblHeaderInfos"
Option Explicit

Private Sub Form_Load()
 Dim Header As New HeaderInfos
 
 Header.FilePath = "G:\Sound\Bon Jovi - It's My Life.mp3"
 Call Header.GetFileInfos

 Me.lstHeaderInfos.Clear
 Me.lstHeaderInfos.AddItem "FilePath: " & vbTab & vbTab & vbTab & _
 Header.FilePath
 Me.lstHeaderInfos.AddItem "FileSize: " & vbTab & vbTab & vbTab & _
 Header.FileSize
 Me.lstHeaderInfos.AddItem "Bitrate: " & vbTab & vbTab & vbTab & _
 Header.Bitrate
 Me.lstHeaderInfos.AddItem "ChannelMode: " & vbTab & vbTab & _
 Header.ChannelMode
 Me.lstHeaderInfos.AddItem "ChannelModeExtention: " & vbTab & _
 Header.ChannelModeExtention
 Me.lstHeaderInfos.AddItem "ChannelModeText: " & vbTab & vbTab & _
 Header.ChannelModeText
 Me.lstHeaderInfos.AddItem "Copyright: " & vbTab & vbTab & _
 Header.Copyright
 Me.lstHeaderInfos.AddItem "CRCProtected: " & vbTab & vbTab & _
 Header.CRCProtected
 Me.lstHeaderInfos.AddItem "Emphasis: " & vbTab & vbTab & Header.Emphasis
 Me.lstHeaderInfos.AddItem "EmphasisText: " & vbTab & vbTab & _
 Header.EmphasisText
 Me.lstHeaderInfos.AddItem "Frames: " & vbTab & vbTab & vbTab & _
 Header.Frames
 Me.lstHeaderInfos.AddItem "FrameSize: " & vbTab & vbTab & _
 Header.FrameSize
 Me.lstHeaderInfos.AddItem "Frequency: " & vbTab & vbTab & _
 Header.Frequency
 Me.lstHeaderInfos.AddItem "Layer: " & vbTab & vbTab & vbTab & _
 Header.Layer
 Me.lstHeaderInfos.AddItem "LayerText: " & vbTab & vbTab & _
 Header.LayerText
 Me.lstHeaderInfos.AddItem "Original: " & vbTab & vbTab & vbTab & _
 Header.Original
 Me.lstHeaderInfos.AddItem "Padding: " & vbTab & vbTab & vbTab & _
 Header.Padding
 Me.lstHeaderInfos.AddItem "PrivateBit: " & vbTab & vbTab & _
 Header.PrivateBit
 Me.lstHeaderInfos.AddItem "Seconds: " & vbTab & vbTab & Header.Seconds
 Me.lstHeaderInfos.AddItem "Version: " & vbTab & vbTab & vbTab & _
 Header.Version
 Me.lstHeaderInfos.AddItem "VersionText: " & vbTab & vbTab & _
 Header.VersionText
End Sub

'-------- Ende Formular "frmMain" alias frmMain.frm --------
'------------- Ende Projektdatei trMP3info.vbp -------------