利用API函数[mciSendString]可以轻松实现MP3音乐文件的播放。下面这段程序实现了MP3播放的大部分常规操作,对其稍加修改,做一个100KB大小的MP3播放器轻而易举
启动VB程序,在窗体上放置6个命令按钮,三个标签,一个公用对话框、一个进度条、一个状态栏和一个计时器,窗本的布置请参考附图
按钮"Open MP3 File"是用来打开对话框选择MP3文件,其他5个按钮分别为Play(播放)、Pause(暂停)、Stopplay(停止播放)、Back(向后跳跃)、Prew(向前跳跃)。Label1用来表示歌曲当前时间;label2放在时度条的最左边,Caption属性为"00:00";lable3放在时度条的右边,用来表示歌曲总长。
下面就可以编写代码了。首先在窗体的"通用声明"部分声明函数 Private Declare Function mciSendString Lib "winmm.dll" Alias "mciSendStringA"(Byval lpstrCommand As String,ByVal lpstrRetumString As String,ByVal uReturnLength As long,ByVal hwndCallback as long) As long
Dim mfn As String
下面就是各个对象的代码了: Private Sub Form_load() mfn="" play.Enabled=False pause.Enabled=False Stopplay.Enabled=False back.Enabled=False prew.Enabled=False Timer1.Enabled=False Timer1.Interval=500 End Sub
Private Sub open_Click() On Error Goto err With CommonDialog1 .CancelError=True .Filter="音乐文件|*.mp3;*.wav;*.mid" .Flags=cdlOFNNoChangeDir And cdlOFNPathMustExist .Action=1 stopplay_Click ''''停止按钮同时可以设备初始化 mfn=.FileName ''''这个程序中文件名一定不能带空格 Form1.Caption=.FileName play.Enabled=True End With play_Click Exit Sub err: End Sub
Private Sub play_Click() On Error Resume Next Dim t As Long t=mciSendString("open " + mfn,0&,0,0) ''''Open后边的空格一定不能丢 Dim ret As String * 128 t=mciSendString("status " + mfn + " length",ret,128,0) ''''显示歌曲总长 ret=Left(ret,8) If ret<>"" Then ProgressBar1.Min=0 ProgressBar1.Max=Val(ret) Label3.Caption=gettime(Val(ret)) End If play.Enabled=False pause.Enabled=True stopplay.Enabled=True back.Enabled=True prew.Enabled=True t=mciSendString("status " + mfn +" mode",ret,128,0) ''''得到设备的当前状态,是播放还是暂停等等 ret=Left(ret,8) StatusBar1.Panels(1).text=ret ''''在状态栏显示播放状态 t=mciSendString("play " + mfn + " form " + Str(ProgressBar1.Value),0&,0,0) ''''开始播放 Timer1.Enabled=True End Sub
Private Sub pause_Click() t%=mciSendString("pause " + mfn,0&,0,0) ''''发出暂停的命令 play.Enable=True pause.Enabled=False stopplay.Enabled=True back.Enabled=False prew.Enabled=False End Sub
Private Sub stopplay_Click() t%=mciSendString("stop " + mfn,0&,0,0) t%=mciSendString("close " + mfn,0&,0,0) ''''停止播放 play.Enabled=True pause.Enabled=False stopplay.Enabled=False back.Enabled=False prew.Enabled=False End Sub
Private Sub back_Click() t%=mciSendString("play " + mfn + " from " + Str(ProgressBar1.Value-(ProgressBar1.Max\10)),0&,0,0) ''''向后跳一小段再播放 End Sub
Private Sub prew_Click() t%=mciSendString("play " + mfn + " from " + Stri(ProgressBar1.Value+(ProgressBar1.Max\10)),0&,0,0) ''''向前跳一小段再播放 End Sub
Private Sub Timer1_Timer() Dim t As Long Dim ret As String * 128 t=mciSendString("status " + mfn + " position",ret,0,0) ''''得到当前播放位置 ret=left(ret,8) ProgressBar1.Value=Val(ret) Label1.Caption=gettime(Val(ret)) ''''显示歌曲当前时间 If ProgressBar1.Value=ProgressBar1.Max Then stopplay_Click End If t=mciSendString("status " + mfn + " mode",ret,128,0) ret=Left(ret,8) StatusBar1.Panels(1).Text=ret End Sub
Private Sub Form_Unload(Cacel As Integer) t%=mciSendString("stop " + mfn,0&,0,0) t%=mciSendString("close " + mfn,0&,0,0) End Sub
Private Function Gettime(position As Long) As String ''''这个函数的功能是把以长整型表示的时间转换为电子钟式的"**:**" Dim min,sec min=position/1000 min=min/60 sec=min-Int(min) min=Int(min) sec=60 * sec / 100 sec=Int(sec * 100) gettime=Str(min) + ":" + Str(sec) End Function
图中5个控制按钮,其实是把字体设为"Webdings",让它们的Caption属性分别为"4" ";" "<" "7" "8" 就可以了
[常用软件]Kugoo轻松帮你将歌曲拷入MP3播放器 [常用软件]利用MyIM来做MP3播放器
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