作者：未知 来源：月光软件站 加入时间：2005-2-28　月光软件站 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 longDim mfn As String 下面就是各个对象的代码了：Private Sub Form_load()mfn=""play.Enabled=Falsepause.Enabled=FalseStopplay.Enabled=Falseback.Enabled=Falseprew.Enabled=FalseTimer1.Enabled=FalseTimer1.Interval=500End Sub Private Sub open_Click()On Error Goto errWith CommonDialog1.CancelError=True.Filter="音乐文件|*.mp3;*.wav;*.mid".Flags=cdlOFNNoChangeDir And cdlOFNPathMustExist.Action=1stopplay_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=.FileNameplay.Enabled=TrueEnd Withplay_ClickExit Suberr:End Sub Private Sub play_Click()On Error Resume NextDim t As Longt=mciSendString("open " + mfn,0&,0,0) 'Open后边的空格一定不能丢Dim ret As String * 128t=mciSendString("status " + mfn + " length",ret,128,0)'显示歌曲总长ret=Left(ret,8)If ret<>"" ThenProgressBar1.Min=0ProgressBar1.Max=Val(ret)Label3.Caption=gettime(Val(ret))End Ifplay.Enabled=Falsepause.Enabled=Truestopplay.Enabled=Trueback.Enabled=Trueprew.Enabled=Truet=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=TrueEnd Sub Private Sub pause_Click()t%=mciSendString("pause " + mfn,0&,0,0)'发出暂停的命令play.Enable=Truepause.Enabled=Falsestopplay.Enabled=Trueback.Enabled=Falseprew.Enabled=FalseEnd 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=Truepause.Enabled=Falsestopplay.Enabled=Falseback.Enabled=Falseprew.Enabled=FalseEnd 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 LongDim ret As String * 128t=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 Thenstopplay_ClickEnd Ift=mciSendString("status " + mfn + " mode",ret,128,0)ret=Left(ret,8)StatusBar1.Panels(1).Text=retEnd 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,secmin=position/1000min=min/60sec=min-Int(min)min=Int(min)sec=60 * sec / 100sec=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

评论