testmm.vb

这是一本用Visual Studio.NET进行多媒体编程的读物

Option Strict Off
Option Explicit On
Friend Class Form1
	Inherits System.Windows.Forms.Form
#Region "Windows 窗体设计器生成的代码"
	Public Sub New()
		MyBase.New()
		If m_vb6FormDefInstance Is Nothing Then
			If m_InitializingDefInstance Then
				m_vb6FormDefInstance = Me
			Else
				Try 
					'对于启动窗体，所创建的第一个实例为默认实例。
					If System.Reflection.Assembly.GetExecutingAssembly.EntryPoint.DeclaringType Is Me.GetType Then
						m_vb6FormDefInstance = Me
					End If
				Catch
				End Try
			End If
		End If
		'此调用是 Windows 窗体设计器所必需的。
		InitializeComponent()
	End Sub
	'窗体重写处置，以清理组件列表。
	Protected Overloads Overrides Sub Dispose(ByVal Disposing As Boolean)
		If Disposing Then
			If Not components Is Nothing Then
				components.Dispose()
			End If
		End If
		MyBase.Dispose(Disposing)
	End Sub
    Private components As System.ComponentModel.IContainer
	'Windows 窗体设计器所必需的
		Public ToolTip1 As System.Windows.Forms.ToolTip
	Public WithEvents Slider1 As AxComctlLib.AxSlider
	Public WithEvents Command4 As System.Windows.Forms.Button
	Public WithEvents Timer1 As System.Windows.Forms.Timer
	Public WithEvents Text1 As System.Windows.Forms.TextBox
	Public WithEvents Command3 As System.Windows.Forms.Button
	Public WithEvents Command2 As System.Windows.Forms.Button
	Public WithEvents CommonDialog1 As AxMSComDlg.AxCommonDialog
	Public WithEvents Command1 As System.Windows.Forms.Button
	Public WithEvents Label3 As System.Windows.Forms.Label
	Public WithEvents Label2 As System.Windows.Forms.Label
	Public WithEvents Label1 As System.Windows.Forms.Label
	'注意：以下过程是 Windows 窗体设计器所必需的
	'可以使用 Windows 窗体设计器来修改它。
	'不要使用代码编辑器来修改它。
	<System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
        Me.components = New System.ComponentModel.Container()
        Dim resources As System.Resources.ResourceManager = New System.Resources.ResourceManager(GetType(Form1))
        Me.Label3 = New System.Windows.Forms.Label()
        Me.Command1 = New System.Windows.Forms.Button()
        Me.Command3 = New System.Windows.Forms.Button()
        Me.Command2 = New System.Windows.Forms.Button()
        Me.CommonDialog1 = New AxMSComDlg.AxCommonDialog()
        Me.Timer1 = New System.Windows.Forms.Timer(Me.components)
        Me.ToolTip1 = New System.Windows.Forms.ToolTip(Me.components)
        Me.Slider1 = New AxComctlLib.AxSlider()
        Me.Command4 = New System.Windows.Forms.Button()
        Me.Text1 = New System.Windows.Forms.TextBox()
        Me.Label1 = New System.Windows.Forms.Label()
        Me.Label2 = New System.Windows.Forms.Label()
        CType(Me.CommonDialog1, System.ComponentModel.ISupportInitialize).BeginInit()
        CType(Me.Slider1, System.ComponentModel.ISupportInitialize).BeginInit()
        Me.SuspendLayout()
        '
        'Label3
        '
        Me.Label3.BackColor = System.Drawing.SystemColors.Control
        Me.Label3.Cursor = System.Windows.Forms.Cursors.Default
        Me.Label3.ForeColor = System.Drawing.Color.Black
        Me.Label3.Location = New System.Drawing.Point(16, 128)
        Me.Label3.Name = "Label3"
        Me.Label3.RightToLeft = System.Windows.Forms.RightToLeft.No
        Me.Label3.Size = New System.Drawing.Size(114, 29)
        Me.Label3.TabIndex = 8
        Me.Label3.Text = "Label3"
        '
        'Command1
        '
        Me.Command1.BackColor = System.Drawing.SystemColors.ScrollBar
        Me.Command1.Cursor = System.Windows.Forms.Cursors.Default
        Me.Command1.ForeColor = System.Drawing.SystemColors.ControlText
        Me.Command1.Location = New System.Drawing.Point(20, 56)
        Me.Command1.Name = "Command1"
        Me.Command1.RightToLeft = System.Windows.Forms.RightToLeft.No
        Me.Command1.Size = New System.Drawing.Size(166, 28)
        Me.Command1.TabIndex = 0
        Me.Command1.Text = "Load and play a file"
        '
        'Command3
        '
        Me.Command3.BackColor = System.Drawing.SystemColors.ScrollBar
        Me.Command3.Cursor = System.Windows.Forms.Cursors.Default
        Me.Command3.ForeColor = System.Drawing.SystemColors.ControlDarkDark
        Me.Command3.Location = New System.Drawing.Point(287, 56)
        Me.Command3.Name = "Command3"
        Me.Command3.RightToLeft = System.Windows.Forms.RightToLeft.No
        Me.Command3.Size = New System.Drawing.Size(62, 28)
        Me.Command3.TabIndex = 2
        Me.Command3.Text = "Stop"
        '
        'Command2
        '
        Me.Command2.BackColor = System.Drawing.SystemColors.ScrollBar
        Me.Command2.Cursor = System.Windows.Forms.Cursors.Default
        Me.Command2.ForeColor = System.Drawing.SystemColors.ControlDarkDark
        Me.Command2.Location = New System.Drawing.Point(205, 56)
        Me.Command2.Name = "Command2"
        Me.Command2.RightToLeft = System.Windows.Forms.RightToLeft.No
        Me.Command2.Size = New System.Drawing.Size(63, 28)
        Me.Command2.TabIndex = 1
        Me.Command2.Text = "Pause"
        '
        'CommonDialog1
        '
        Me.CommonDialog1.Enabled = True
        Me.CommonDialog1.Location = New System.Drawing.Point(430, 120)
        Me.CommonDialog1.Name = "CommonDialog1"
        Me.CommonDialog1.OcxState = CType(resources.GetObject("CommonDialog1.OcxState"), System.Windows.Forms.AxHost.State)
        Me.CommonDialog1.Size = New System.Drawing.Size(26, 26)
        Me.CommonDialog1.TabIndex = 6
        '
        'Timer1
        '
        Me.Timer1.Interval = 250
        '
        'Slider1
        '
        Me.Slider1.Location = New System.Drawing.Point(10, 93)
        Me.Slider1.Name = "Slider1"
        Me.Slider1.OcxState = CType(resources.GetObject("Slider1.OcxState"), System.Windows.Forms.AxHost.State)
        Me.Slider1.Size = New System.Drawing.Size(442, 28)
        Me.Slider1.TabIndex = 4
        '
        'Command4
        '
        Me.Command4.BackColor = System.Drawing.SystemColors.Control
        Me.Command4.Cursor = System.Windows.Forms.Cursors.Default
        Me.Command4.ForeColor = System.Drawing.SystemColors.ControlDarkDark
        Me.Command4.Location = New System.Drawing.Point(369, 56)
        Me.Command4.Name = "Command4"
        Me.Command4.RightToLeft = System.Windows.Forms.RightToLeft.No
        Me.Command4.Size = New System.Drawing.Size(62, 28)
        Me.Command4.TabIndex = 5
        Me.Command4.Text = "Exit"
        '
        'Text1
        '
        Me.Text1.AcceptsReturn = True
        Me.Text1.AutoSize = False
        Me.Text1.BackColor = System.Drawing.Color.Black
        Me.Text1.Cursor = System.Windows.Forms.Cursors.IBeam
        Me.Text1.ForeColor = System.Drawing.Color.Yellow
        Me.Text1.Location = New System.Drawing.Point(20, 9)
        Me.Text1.MaxLength = 0
        Me.Text1.Name = "Text1"
        Me.Text1.RightToLeft = System.Windows.Forms.RightToLeft.No
        Me.Text1.Size = New System.Drawing.Size(432, 29)
        Me.Text1.TabIndex = 3
        Me.Text1.Text = "Text1"
        '
        'Label1
        '
        Me.Label1.BackColor = System.Drawing.SystemColors.Control
        Me.Label1.Cursor = System.Windows.Forms.Cursors.Default
        Me.Label1.ForeColor = System.Drawing.Color.Black
        Me.Label1.Location = New System.Drawing.Point(136, 128)
        Me.Label1.Name = "Label1"
        Me.Label1.RightToLeft = System.Windows.Forms.RightToLeft.No
        Me.Label1.Size = New System.Drawing.Size(112, 29)
        Me.Label1.TabIndex = 6
        Me.Label1.Text = "Label1"
        '
        'Label2
        '
        Me.Label2.BackColor = System.Drawing.SystemColors.Control
        Me.Label2.Cursor = System.Windows.Forms.Cursors.Default
        Me.Label2.ForeColor = System.Drawing.Color.Black
        Me.Label2.Location = New System.Drawing.Point(264, 128)
        Me.Label2.Name = "Label2"
        Me.Label2.RightToLeft = System.Windows.Forms.RightToLeft.No
        Me.Label2.Size = New System.Drawing.Size(226, 29)
        Me.Label2.TabIndex = 7
        Me.Label2.Text = "Label2"
        '
        'Form1
        '
        Me.AutoScaleBaseSize = New System.Drawing.Size(6, 14)
        Me.BackColor = System.Drawing.SystemColors.ScrollBar
        Me.ClientSize = New System.Drawing.Size(460, 143)
        Me.Controls.AddRange(New System.Windows.Forms.Control() {Me.Slider1, Me.Command4, Me.Text1, Me.Command3, Me.Command2, Me.CommonDialog1, Me.Command1, Me.Label3, Me.Label2, Me.Label1})
        Me.ForeColor = System.Drawing.SystemColors.ActiveCaption
        Me.Location = New System.Drawing.Point(3, 22)
        Me.MaximizeBox = False
        Me.MinimizeBox = False
        Me.Name = "Form1"
        Me.Text = "MIDIPlayer "
        CType(Me.CommonDialog1, System.ComponentModel.ISupportInitialize).EndInit()
        CType(Me.Slider1, System.ComponentModel.ISupportInitialize).EndInit()
        Me.ResumeLayout(False)

    End Sub
#End Region 
#Region "升级支持"
	Private Shared m_vb6FormDefInstance As Form1
	Private Shared m_InitializingDefInstance As Boolean
	Public Shared Property DefInstance() As Form1
		Get
			If m_vb6FormDefInstance Is Nothing OrElse m_vb6FormDefInstance.IsDisposed Then
				m_InitializingDefInstance = True
				m_vb6FormDefInstance = New Form1()
				m_InitializingDefInstance = False
			End If
			DefInstance = m_vb6FormDefInstance
		End Get
		Set
			m_vb6FormDefInstance = Value
		End Set
	End Property
#End Region 
	Dim Multimedia As Mmedia = New Mmedia ' 定义一个对象
	Dim NewPosition As Single
	Dim DisplayingInfo As String
	Dim CrossNum As Short
	
	Private Sub Command1_Click(ByVal eventSender As System.Object, ByVal eventArgs As System.EventArgs) Handles Command1.Click ' 这个过程打开并播放一个多媒体文件
		With CommonDialog1
			.Filter = "WaveAudio (*.wav)|*.wav|Midi (*.mid)|*.mid|Video files (*.avi)|*.avi"
			.FilterIndex = 2
			.ShowOpen()
		End With
		
		If CommonDialog1.FileName <> "" Then
			Multimedia.mmClose()
			Multimedia.mmOpen(CommonDialog1.FileName)
			Timer1.Enabled = True ' 使计时器开始计时
			Slider1.Min = 0 ' 设置Slider1的值域
			Slider1.Max = Multimedia.Length ' 设置Slider1的值域
			Multimedia.mmPlay()
			NewPosition = 0
			DisplayingInfo = "正在播放：" & CommonDialog1.FileName & ""
			Text1.Text = DisplayingInfo
			Label3.Text = "总长度" & Str(Multimedia.Length)
		End If
	End Sub
	
	
	Private Sub Command2_Click(ByVal eventSender As System.Object, ByVal eventArgs As System.EventArgs) Handles Command2.Click ' 这个过程在播放和暂停之间切换
		If Command2.Text = "Pause" Then
			Multimedia.mmPause()
			Timer1.Enabled = False ' 当暂停播放时，计时器Timer1也停止计时
			Command2.Text = "Continue"
		Else
			Timer1.Enabled = True
			Multimedia.mmPlay()
			Command2.Text = "Pause"
		End If
	End Sub
	
	Private Sub Command3_Click(ByVal eventSender As System.Object, ByVal eventArgs As System.EventArgs) Handles Command3.Click '这个过程在播放、停止和重播之间切换
		Select Case Command3.Text
			Case "Stop"
				Multimedia.mmStop()
				Command3.Text = "Play"
				Timer1.Enabled = False
			Case "Play"
				Multimedia.mmPlay()
				Command3.Text = "Stop"
				Timer1.Enabled = True
			Case "Replay"
				Multimedia.mmSeek(0)
				Multimedia.mmPlay()
				Command3.Text = "Stop"
				Text1.Text = DisplayingInfo
				Timer1.Enabled = True
		End Select
		
	End Sub
	
	Private Sub Command4_Click(ByVal eventSender As System.Object, ByVal eventArgs As System.EventArgs) Handles Command4.Click '这个过程用以退出程序
		Multimedia.mmClose()
		End
	End Sub
	
	Private Sub Form1_Load(ByVal eventSender As System.Object, ByVal eventArgs As System.EventArgs) Handles MyBase.Load ' 这个过程用以初始化有关变量
		NewPosition = 0
		CrossNum = 0
		Slider1.SelectRange = True
		Label1.Text = ""
		Label2.Text = ""
		Label3.Text = ""
		Text1.Text = "请选择歌曲"
	End Sub
	
	'UPGRADE_WARNING: Form 事件 Form1.Unload 具有新的行为。 单击以获得更多信息：ms-help://MS.MSDNVS/vbcon/html/vbup2065.htm
	Private Sub Form1_Closed(ByVal eventSender As System.Object, ByVal eventArgs As System.EventArgs) Handles MyBase.Closed
		Multimedia.mmClose()
	End Sub
	
	Private Sub Slider1_MouseDownEvent(ByVal eventSender As System.Object, ByVal eventArgs As AxComctlLib.ISliderEvents_MouseDownEvent) Handles Slider1.MouseDownEvent
		If eventArgs.Shift = 1 Then
			'Multimedia.mmStop
			Timer1.Enabled = False
			'Slider1.SelStart = Slider1.Value
			'将先前的 SelLength （如果有）设置为 0.
			'Slider1.SelLength = 0
		End If
	End Sub
	
	Private Sub Slider1_MouseUpEvent(ByVal eventSender As System.Object, ByVal eventArgs As AxComctlLib.ISliderEvents_MouseUpEvent) Handles Slider1.MouseUpEvent
		If eventArgs.Shift = 1 Then
			NewPosition = Slider1.Value
			Label1.Text = CStr(Slider1.Value)
			Multimedia.mmSeek(NewPosition)
			Multimedia.mmPlay()
			Timer1.Enabled = True
		Else
			Slider1.SelLength = 0
		End If
	End Sub
	
	Private Sub Timer1_Tick(ByVal eventSender As System.Object, ByVal eventArgs As System.EventArgs) Handles Timer1.Tick ' 这个过程定时产生系统状态更新事件
		CrossNum = (CrossNum + 1) Mod 26
		If CrossNum >= 24 Then
			Label2.Text = ""
		End If
		Label2.Text = Label2.Text & "*"
        Label1.Text = "播放到 " & CStr(Multimedia.Position)
		Slider1.Value = Multimedia.Position
		If Multimedia.Position = Multimedia.Length Then
			Text1.Text = "请选择歌曲"
			Command3.Text = "Replay"
			Label1.Text = ""
			Label2.Text = ""
			Label3.Text = ""
			Timer1.Enabled = False
		End If
	End Sub
End Class