Detect if CD door opens

[blindlizard]

How can I detect if the CD door opens while my app is running? I am makig something for my son, but I want the app to die if he opens the CD door. That way when he puts the next CD in, it will play the next app, and I don't have to worry about him getting confussed.

[laserman]

This opens the cddoor via a button but you can implement the code wherever suits you.
Hope this helps.

Private Sub Command1_Click()
retvalue = mciSendString("set CDAudio door open", _
returnstring, 127, 0)
MsgBox ("The Cddoor has opened,Your application will terminate"), vbInformation

[blindlizard]

No, I don't need to open the door, I need to know if the door has been opened. I need to know if he pushed the eject button on the CD drive, then kill the app.

[manavo11]

There was a post about this a short while ago. I'll search for it. I had an attachment there...

[manavo11]

Here it is (look attachment in one of my posts ) : http://www.vbforums.com/showthread.p...hreadid=253107

[blindlizard]

Ok, I downloaded the cdspy project, but am a little lost at what I am looking at. Do you think you can walk me through it. When I run it nothing happens, should it? I see the Function ProcessDeviceChange that looks like it will tell if a cd is inserted or removed, but I am not sure what to pass it. Thanks.

[Shawn N]

Strange how much my coding on that post looks like what you posted, manavo.

[manavo11]

Hey don't look at me! You might have noticed that the code is from www.allapi.net (http://www.mentalis.org/vbexamples/v...ategory=SOURCE)

[manavo11]

Well, what it does is subclass the form and process the messages sent.


When media is inserted or removed then you process the messages that are sent to the form (ProcessDeviceChange) to detect which drive it was and if it was inserted or removed. When you first run the application you won't see anything. You will see stuff in the listbox when you open/close the cdrom drives...

Is that any better?

[blindlizard]

ah, ok i see now. But, here is what I am doing. I have an application burnt to a CD. This application allows my son to choose from the movies (also bunt to the CD) and open them with the default player for the file type, ie .avi opens with Windows Media Player. He has enough movies to fit about 8 CDs. When he puts one it, it runs my application (burnt on the CD) and allows him to navigate and play the movies on the CD. What I want is after he puts a CD in and it runs my application, that if he decides that is not the CD he wants, and opens the CD tray, that the application will terminate. This way when he puts in another CD, the application on it will run and he wont accidentally use the old app from the CD that is no longer in the drive.

[manavo11]

Wouldn't the app end if the cd was ejected? Anyway, what you can do is this :

Use all the subclassing stuff on your app, then when one of the drives on your computer is ejected all the code in ProcessDeviceChange will execute. Instead of the listbox stuff you can use the eject code to compare this Chr$(FirstDriveFromMask(DBVol.dbcv_unitmask)) with this Left$(App.Path, 1) (to get the drive letter that your app is in. You can probably skip this part if you have only one drive). If it is the same, unload your form. I think that'll work

[Shawn N]

If I was doing this project, I'd check at startup to see if my app was already running. You could use FindWindow to look for your application (I'm not sure about PrevInstance).


If it was already running, you could just unload.

[blindlizard]

manavo11, I think that will work, thanks I'll try that.

Shawn N, that would be easiest, but I don't think it will do what I need because, if he ejects the CD and dosent put a new one in, the app will stay running. Then if he tries to open one of the movies it will error out because the path won't exist anymore.

[Shawn N]

Nothing a little error handling couldn't handle.

[blindlizard]

Yeah, I hear you, but I can't very well popup a message to him because he can't read. I think it would be less confusing in the long run to lhave the app go away. He can understand that you put the CD in, play movies, and remove the CD. Oh, and my 2 year old is using these now too.

[Shawn N]

Yea, I was thinking about that right after my post.

[manavo11]

Let me know how it works out