当前曲目的播放时间.frm

Windows API函数,希望大伙有用哦

VERSION 5.00
Begin VB.Form Form5 
   Caption         =   "Form5"
   ClientHeight    =   1140
   ClientLeft      =   60
   ClientTop       =   345
   ClientWidth     =   5175
   LinkTopic       =   "Form3"
   ScaleHeight     =   1140
   ScaleWidth      =   5175
   StartUpPosition =   3  '窗口缺省
   Begin VB.Timer Timer1 
      Enabled         =   0   'False
      Interval        =   1000
      Left            =   4650
      Top             =   150
   End
   Begin VB.TextBox Text2 
      Alignment       =   1  'Right Justify
      Height          =   305
      Left            =   3390
      TabIndex        =   6
      Text            =   "Text2"
      Top             =   120
      Width           =   1215
   End
   Begin VB.TextBox Text1 
      Alignment       =   1  'Right Justify
      Height          =   305
      Left            =   1170
      Locked          =   -1  'True
      TabIndex        =   4
      Text            =   "Text1"
      Top             =   120
      Width           =   915
   End
   Begin VB.CommandButton Command4 
      Caption         =   "停止播放"
      Height          =   315
      Left            =   3720
      TabIndex        =   3
      Top             =   690
      Width           =   1185
   End
   Begin VB.CommandButton Command3 
      Caption         =   "下一曲目>>"
      Height          =   315
      Left            =   2520
      TabIndex        =   2
      Top             =   690
      Width           =   1185
   End
   Begin VB.CommandButton Command2 
      Caption         =   "<<上一曲目"
      Height          =   315
      Left            =   1320
      TabIndex        =   1
      Top             =   690
      Width           =   1185
   End
   Begin VB.CommandButton Command1 
      Caption         =   "播    放"
      Height          =   315
      Left            =   120
      TabIndex        =   0
      Top             =   690
      Width           =   1185
   End
   Begin VB.Label Label2 
      AutoSize        =   -1  'True
      Caption         =   "播放时间："
      Height          =   180
      Left            =   2400
      TabIndex        =   7
      Top             =   180
      Width           =   900
   End
   Begin VB.Label Label1 
      AutoSize        =   -1  'True
      Caption         =   "当前曲目："
      Height          =   180
      Left            =   210
      TabIndex        =   5
      Top             =   180
      Width           =   900
   End
End
Attribute VB_Name = "Form5"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
Option Explicit
'  API函数声明
Private Declare Function mciSendString Lib "winmm.dll" Alias "mciSendStringA" (ByVal lpstrCommand As String, ByVal lpstrReturnString As String, ByVal uReturnLength As Long, ByVal hwndCallback As Long) As Long
    Dim S As String, Tracks As Integer, CurTrack As Integer
    Dim T1 As Date, T2 As Date
    Dim Total As Integer, D As String
    Dim Tm As Integer, Ts As Integer, Tsd As String
Private Sub Form_Load()
'  打开 CD 设备
    mciSendString "Open cdaudio alias CDRom", vbNullString, 0, 0
    S = String(256, Chr(0))
    mciSendString "Status CDRom number of tracks", S, Len(S), 0
    Tracks = Val(S)
'  将播放曲目定位在第一首乐曲
    CurTrack = 1
    mciSendString "Status CDRom position track " & CurTrack, S, Len(S), 0
    Text1 = CurTrack
    Text2 = "0:00"
End Sub
Private Sub Command1_Click()
'  播放音乐
    Text2 = "0:00"
    mciSendString "Status CDRom Length track " & CurTrack, S, Len(S), 0
    Total = Val(Mid(S, 1, 2)) * 60 + Val(Mid(S, 4, 2))
    mciSendString "Play CDRom", vbNullString, 0, 0
    T1 = Time
    Timer1.Enabled = True
End Sub
Private Sub Command2_Click()
'  播放上一曲目
    Text2 = "0:00"
      If CurTrack > 1 Then
          CurTrack = CurTrack - 1
        Else
          CurTrack = Tracks
      End If
    Text1 = CurTrack
    mciSendString "Status CDRom Length track " & CurTrack, S, Len(S), 0
    Total = Val(Mid(S, 1, 2)) * 60 + Val(Mid(S, 4, 2))
    mciSendString "Status CDRom position track " & CurTrack, S, Len(S), 0
    mciSendString "Play CDRom from " & Left(S, 8), vbNullString, 0, 0
    T1 = Time
    Timer1.Enabled = True
End Sub
Private Sub Command3_Click()
'  播放下一曲目
    Text2 = "0:00"
      If CurTrack < Tracks Then
          CurTrack = CurTrack + 1
        Else
          CurTrack = 1
      End If
    Text1 = CurTrack
    mciSendString "Status CDRom Length track " & CurTrack, S, Len(S), 0
    Total = Val(Mid(S, 1, 2)) * 60 + Val(Mid(S, 4, 2))
    mciSendString "Status CDRom position track " & CurTrack, S, Len(S), 0
    mciSendString "Play CDRom from " & Left(S, 8), vbNullString, 0, 0
    T1 = Time
    Timer1.Enabled = True
End Sub
Private Sub Command4_Click()
'  停止播放
    mciSendString "Stop CDRom", vbNullString, 0, 0
    Timer1.Enabled = False
End Sub
Private Sub Timer1_Timer()
'  定时过程，得到乐曲当前实际播放时间
  T2 = Time
  D = DateDiff("s", T1, T2)
  If D = Total Then
    Timer1.Enabled = False
    mciSendString "Stop CDRom", vbNullString, 0, 0
  End If
'  秒化为"分"、"秒"
  If D > 59 Then
    Tm = D \ 60
    Ts = D - 60 * Tm
    If Ts < 10 Then
     Tsd = "0" + CStr(Ts)
     Else
     Tsd = CStr(Ts)
    End If
    Else
    Tm = "00"
    Ts = D
     If Ts < 10 Then
     Tsd = "0" + CStr(Ts)
     Else
     Tsd = CStr(Ts)
    End If
  End If
  Text2 = CStr(Tm) + ":" + Tsd
End Sub