Programming Forums > Application Development > Visual Basic .NET

john Wesley · Jun 23rd, 2006, 9:00 AM

Hello, and good afternoon;

I plead, May I ask for help on the subject of the MCI Device.
I started a program that is an audio player for the file type *.mp3, using the MCI I have it loading a track, playing a track, pausing, resuming and stopping, also I am for now, using a scrollbar as a timing guide as to which point of the file the player is at; this works but only as I have explained and does not work in the way i would like it to.

My problem lies with 'seeking' back and forth through the track. i can grab the scroller and use it to set the players place in the file (while it is playing, otherwise if you set it in the centre then play it will jump back to the start).
On using the left or Right scrollbar 'buttons' however to try and 'fast-forward' or 're-wind' it simply holds the file in same place, i.e not re-winding but not letting it go any further, resulting in the audio you here repeatedly skipping back and forth over the timespan of one second or so.

Could anybody give me any advice of getting the scrollbar to stay realtime with the file in play but also allow me to seek through the track either way I wish by clicking the intended direction?

I am at work and do not have my code in front of me so I send all apologies if this is completely wrong, but I think the general idea is better than nothing....

sets the bars maximum to the length of the file.

(Toggle Plain Text)

HScrollBar1.Value.Maximum = Val(returnData)

plays file from start if loaded.

(Toggle Plain Text)

retVal = mciSendString("play thesong", 0, 0, 0)

I understand there is a 'seek to' command string for the MCI Device though i cant seem to set it...for example...

(Toggle Plain Text)

retVal = mciSendString("seek thesong to", 0, 0, 0)

I have tried setting the milliseconds all over this code but have no luck and can only presume i need some flags to acompany this procedure, setting it so general buttons could do it would be just as good.

-coughs- um this got long, sorry. Thanks though, for any direction.
John Wesley Hardin'

p.s If i could/should or need to explain anything differently please state so.

melbolt · Jun 23rd, 2006, 11:29 AM

here's an example i found, i know its a bit different than what you're working on, but you still should able to use the same concepts on yours.

(Toggle Plain Text)

Function FastForward(Spd%)
Dim s As String * 40
SetFormat_milliseconds
mciSendString "status cd position wait", s, Len(s), 0
CheckIfPlaying%
If CheckIfPlaying = 1 Then
mciSendString "play cd from " & CStr(CLng(s) + Spd), 0, 0, 0
Else
mciSendString "seek cd to " & CStr(CLng(s) + Spd), 0, 0, 0
End If
SetFormat_tmsf
End Function

Function ReWind(Spd%)
Dim s As String * 40
SetFormat_milliseconds
mciSendString "status cd position wait", s, Len(s), 0
CheckIfPlaying%
If CheckIfPlaying = 1 Then
mciSendString "play cd from " & CStr(CLng(s) - Spd), 0, 0, 0
Else
mciSendString "seek cd to " & CStr(CLng(s) - Spd), 0, 0, 0
End If
SetFormat_tmsf
End Function


Private Sub Command6_Click()
Snd.ReWind Val(Text2) * 1000
End Sub

Private Sub Command7_Click()
Snd.FastForward Val(Text2) * 1000
End Sub

source: http://cuinl.tripod.com/Tips/cdplayer.htm

john Wesley · Jun 24th, 2006, 11:26 AM

Great Stuff melbolt, Il try putting this into action. I've found the MCI Device extremely useful for media but it can be tricky at times when these trivial situtations pop up, and the MSDN Library's information on this is scarce other than giving you the initial command.
Thanks Alot.

John Wesley Hardin'

Jun 23rd, 2006, 9:00 AM	#1
john Wesley Hobbyist Programmer Join Date: May 2006 Location: United Kingdom Posts: 119 Rep Power: 3	MCI SendString query Hello, and good afternoon; I plead, May I ask for help on the subject of the MCI Device. I started a program that is an audio player for the file type *.mp3, using the MCI I have it loading a track, playing a track, pausing, resuming and stopping, also I am for now, using a scrollbar as a timing guide as to which point of the file the player is at; this works but only as I have explained and does not work in the way i would like it to. My problem lies with 'seeking' back and forth through the track. i can grab the scroller and use it to set the players place in the file (while it is playing, otherwise if you set it in the centre then play it will jump back to the start). On using the left or Right scrollbar 'buttons' however to try and 'fast-forward' or 're-wind' it simply holds the file in same place, i.e not re-winding but not letting it go any further, resulting in the audio you here repeatedly skipping back and forth over the timespan of one second or so. Could anybody give me any advice of getting the scrollbar to stay realtime with the file in play but also allow me to seek through the track either way I wish by clicking the intended direction? I am at work and do not have my code in front of me so I send all apologies if this is completely wrong, but I think the general idea is better than nothing.... sets the bars maximum to the length of the file. (Toggle Plain Text) HScrollBar1.Value.Maximum = Val(returnData) HScrollBar1.Value.Maximum = Val(returnData) plays file from start if loaded. (Toggle Plain Text) retVal = mciSendString("play thesong", 0, 0, 0) retVal = mciSendString("play thesong", 0, 0, 0) I understand there is a 'seek to' command string for the MCI Device though i cant seem to set it...for example... (Toggle Plain Text) retVal = mciSendString("seek thesong to", 0, 0, 0) retVal = mciSendString("seek thesong to", 0, 0, 0) I have tried setting the milliseconds all over this code but have no luck and can only presume i need some flags to acompany this procedure, setting it so general buttons could do it would be just as good. -coughs- um this got long, sorry. Thanks though, for any direction. John Wesley Hardin' p.s If i could/should or need to explain anything differently please state so. __________________ Mona Lisa must of had the highway blues you can tell by the way she smiles..

Jun 23rd, 2006, 11:29 AM	#2
melbolt Professional Programmer Join Date: Feb 2005 Location: PA, USA Posts: 254 Rep Power: 4	here's an example i found, i know its a bit different than what you're working on, but you still should able to use the same concepts on yours. (Toggle Plain Text) Function FastForward(Spd%) Dim s As String * 40 SetFormat_milliseconds mciSendString "status cd position wait", s, Len(s), 0 CheckIfPlaying% If CheckIfPlaying = 1 Then mciSendString "play cd from " & CStr(CLng(s) + Spd), 0, 0, 0 Else mciSendString "seek cd to " & CStr(CLng(s) + Spd), 0, 0, 0 End If SetFormat_tmsf End Function Function ReWind(Spd%) Dim s As String * 40 SetFormat_milliseconds mciSendString "status cd position wait", s, Len(s), 0 CheckIfPlaying% If CheckIfPlaying = 1 Then mciSendString "play cd from " & CStr(CLng(s) - Spd), 0, 0, 0 Else mciSendString "seek cd to " & CStr(CLng(s) - Spd), 0, 0, 0 End If SetFormat_tmsf End Function Private Sub Command6_Click() Snd.ReWind Val(Text2) * 1000 End Sub Private Sub Command7_Click() Snd.FastForward Val(Text2) * 1000 End Sub Function FastForward(Spd%) Dim s As String * 40 SetFormat_milliseconds mciSendString "status cd position wait", s, Len(s), 0 CheckIfPlaying% If CheckIfPlaying = 1 Then mciSendString "play cd from " & CStr(CLng(s) + Spd), 0, 0, 0 Else mciSendString "seek cd to " & CStr(CLng(s) + Spd), 0, 0, 0 End If SetFormat_tmsf End Function Function ReWind(Spd%) Dim s As String * 40 SetFormat_milliseconds mciSendString "status cd position wait", s, Len(s), 0 CheckIfPlaying% If CheckIfPlaying = 1 Then mciSendString "play cd from " & CStr(CLng(s) - Spd), 0, 0, 0 Else mciSendString "seek cd to " & CStr(CLng(s) - Spd), 0, 0, 0 End If SetFormat_tmsf End Function Private Sub Command6_Click() Snd.ReWind Val(Text2) * 1000 End Sub Private Sub Command7_Click() Snd.FastForward Val(Text2) * 1000 End Sub source: http://cuinl.tripod.com/Tips/cdplayer.htm __________________ I have never let my schooling interfere with my education. -Mark Twain- Xbox live gamertag: melbolt

Jun 24th, 2006, 11:26 AM	#3
john Wesley Hobbyist Programmer Join Date: May 2006 Location: United Kingdom Posts: 119 Rep Power: 3	Great Stuff melbolt, Il try putting this into action. I've found the MCI Device extremely useful for media but it can be tricky at times when these trivial situtations pop up, and the MSDN Library's information on this is scarce other than giving you the initial command. Thanks Alot. John Wesley Hardin' __________________ Mona Lisa must of had the highway blues you can tell by the way she smiles..

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Programming Forums > Application Development > Visual Basic .NET

MCI SendString query