Multiple instances of FileSystemWatch er ??????

[David]

I have been working on trying to write a directory watcher service.
One of the requirments is that it be able to watch multiple
directories, not sub directories of one parent directory, but just
multiple directories.

I have hit a snag and don't know how to get around it.

Basically I read in a list of directories from the app.config and stuff
them into an array, so that I have something like this:
sDirsToWatch[0] = "C:\Temp"
sDirsToWatch[1] = "D:\Temp"

Then I do the following

For (i = 0; i < sDirsToWatch.Le ngth; i++)
{
FileSystemWatch er myWatcher = new System.IO.FileS ystemWatcher();
myWatcher.Notif yFilter = NotifyFilters.D irectoryName |
NotifyFilters.F ileName | NotifyFilters.A ttributes;
myWatcher.Delet ed += new FileSystemEvent Handler(LogDele ted);
myWatcher.Path = sDirsToWatch[i];
myWatcher.Enabl eRaisingEvents = true;
}

Now when it gets to either the .Path line or to when it gets to the
..EnableRaising Events for the 2nd directory, I get an error: Error
reading the D:\Temp directory

I think what is happening is that all of the objects that I am creating
are named the same, so its causing problems.

So my question is, how do I dynamically name my FileSystemWatch er
object ?

Any help would be most appreciated.

Thanks

David

[Nicholas Paldino [.NET/C# MVP]]

David,

It doesn't look like this is the case. Are you running this in a
service? Are you sure that you have access to the drive itself (if it is a
service, then it might not, by default). Also, are you sure that the
directory itself exists?

Hope this helps.
--
- Nicholas Paldino [.NET/C# MVP]
- mv*@spam.guard. caspershouse.co m

"David" <da************ **@gmail.com> wrote in message
news:11******** *************@g 14g2000cwa.goog legroups.com...

I have been working on trying to write a directory watcher service.
One of the requirments is that it be able to watch multiple
directories, not sub directories of one parent directory, but just
multiple directories.

I have hit a snag and don't know how to get around it.

Basically I read in a list of directories from the app.config and stuff
them into an array, so that I have something like this:
sDirsToWatch[0] = "C:\Temp"
sDirsToWatch[1] = "D:\Temp"

Then I do the following

For (i = 0; i < sDirsToWatch.Le ngth; i++)
{
FileSystemWatch er myWatcher = new System.IO.FileS ystemWatcher();
myWatcher.Notif yFilter = NotifyFilters.D irectoryName |
NotifyFilters.F ileName | NotifyFilters.A ttributes;
myWatcher.Delet ed += new FileSystemEvent Handler(LogDele ted);
myWatcher.Path = sDirsToWatch[i];
myWatcher.Enabl eRaisingEvents = true;
}

Now when it gets to either the .Path line or to when it gets to the
.EnableRaisingE vents for the 2nd directory, I get an error: Error
reading the D:\Temp directory

I think what is happening is that all of the objects that I am creating
are named the same, so its causing problems.

So my question is, how do I dynamically name my FileSystemWatch er
object ?

Any help would be most appreciated.

Thanks

David

[David]

Nicholas:

Not running this as a service yet, until I get the code nailed down I
am doing it from a Windows Form application, but it will be moved to a
service once I get the code working.

Both directories exist on my local hard drive and I can freely copy and
delete files from them.

Thanks for the help

David

[Andy]

David,

I don't think you can have one watcher watching multiple directories.
Try creating a new instance for each directory you would like to watch.

I think the problem is that everytime you hit the top of your loop, you
make myWatcher point to a new object, and the old one gets destoryed
since nothing is referencing it any longer.

Andy

[Nicholas Paldino [.NET/C# MVP]]

David,

The naming of the file system watchers is not an issue, since you create
a new one each time you iterate through the loop. Are there any more
details to the exception?

If you want to hold all the instances, you can create an array of file
system watchers, and populate each element of the array with a reference to
a different instance.
--
- Nicholas Paldino [.NET/C# MVP]
- mv*@spam.guard. caspershouse.co m

"David" <da************ **@gmail.com> wrote in message
news:11******** **************@ z14g2000cwz.goo glegroups.com.. .

Nicholas:

Not running this as a service yet, until I get the code nailed down I
am doing it from a Windows Form application, but it will be moved to a
service once I get the code working.

Both directories exist on my local hard drive and I can freely copy and
delete files from them.

Thanks for the help

David

[David]

Andy:

I agree with what you are saying, I'm pretty sure that is what the
problem is.

What I don't know how to do is dynamically name the FileSystemWatch er.
Since I am using a for statement, I was hoping I could somehow derive
the name of the object every time the loop iterates, so for example
since there are only 2 directories in the array, I would end up with
FileSystemWatch er objects named: myWatcher0, myWatcher1.

But if I try and build a string for the FileSystemWatch er object name
and then reference that variable on the line where I say
FileSystemWatch er myWatcher = new System.IO.FileS ystemWatcher(); , I get
an error during compile time.

So I guess that the question is given this line of code:
FileSystemWatch er myWatcher = new System.IO.FileS ystemWatcher();

How do I dynamically name the object myWatcher so that when it iterates
through the for, its not always the same name ?

[Ignacio Machin \( .NET/ C# MVP \)]

Hi,

I would change a little your code:

ArrayList watchers = new ArrayList();

For (i = 0; i < sDirsToWatch.Le ngth; i++)
{
FileSystemWatch er myWatcher = new System.IO.FileS ystemWatcher();
myWatcher.Notif yFilter = NotifyFilters.D irectoryName |
NotifyFilters.F ileName | NotifyFilters.A ttributes;
myWatcher.Delet ed += new FileSystemEvent Handler(LogDele ted);
myWatcher.Path = sDirsToWatch[i];
myWatcher.
myWatcher.Enabl eRaisingEvents = true;
watchers.Add( myWatcher);
}

Try it, basically I'm keeping the references to them. ( in case you need to
disable one afterwards )

Also, and here is where your error may be, rewrite it like this:

sDirsToWatch[0] = @"C:\Temp";
sDirsToWatch[1] = @"D:\Temp";

cheers;
--
Ignacio Machin,
ignacio.machin AT dot.state.fl.us
Florida Department Of Transportation

"David" <da************ **@gmail.com> wrote in message
news:11******** *************@g 14g2000cwa.goog legroups.com...

I have been working on trying to write a directory watcher service.
One of the requirments is that it be able to watch multiple
directories, not sub directories of one parent directory, but just
multiple directories.

I have hit a snag and don't know how to get around it.

Basically I read in a list of directories from the app.config and stuff
them into an array, so that I have something like this:
sDirsToWatch[0] = "C:\Temp"
sDirsToWatch[1] = "D:\Temp"

Then I do the following

For (i = 0; i < sDirsToWatch.Le ngth; i++)
{
FileSystemWatch er myWatcher = new System.IO.FileS ystemWatcher();
myWatcher.Notif yFilter = NotifyFilters.D irectoryName |
NotifyFilters.F ileName | NotifyFilters.A ttributes;
myWatcher.Delet ed += new FileSystemEvent Handler(LogDele ted);
myWatcher.Path = sDirsToWatch[i];
myWatcher.Enabl eRaisingEvents = true;
}

Now when it gets to either the .Path line or to when it gets to the
.EnableRaisingE vents for the 2nd directory, I get an error: Error
reading the D:\Temp directory

I think what is happening is that all of the objects that I am creating
are named the same, so its causing problems.

So my question is, how do I dynamically name my FileSystemWatch er
object ?

Any help would be most appreciated.

Thanks

David

[Andy]

Dave,

I think what you're saying you want is to name the object using the
value stored in a string.

Something like:
string nameIt = "watcher01" ;

FileSystemWatch er nameIt = new ...

If thats what you want, you can't really do that..however you could
store your watcher objects in a HashTable.

HashTable watchers = new HashTable();
FileSystemWatch er watcher;

for( int i = 0 ; i < 2 ; i += 1 0 {
watcher = new FileSystemWatch er();
// set its properties
watchers.Add( "watcher" + i.ToSring(), watcher );
}

Then access them like so
watcher = (FileSystemWatc her)watchers[ "watcher1" ];

Andy

[David]

Ignacio:

Thanks for the reply, I did try that originally, but that doesn't seem
to work either, basically on the 2nd interation into the loop when it
gets to the line for myWatcher.Enabl eRaisingEvents = true; it throws an
error.

Here is the code exactly:

int i;
string sAppRead = @"C:\FileWatche rTest2, C:\FileWatcherT est";

string [] sDirsToWatch;

sDirsToWatch = sAppRead.Split( ',');

ArrayList FileWatchers = new ArrayList();

for (i = 0; i < sDirsToWatch.Le ngth; i++)
{
FileSystemWatch er myWatcher = new System.IO.FileS ystemWatcher();
myWatcher.Notif yFilter = NotifyFilters.D irectoryName |
NotifyFilters.F ileName | NotifyFilters.A ttributes;
myWatcher.Delet ed += new FileSystemEvent Handler(LogDele ted);
myWatcher.Path = sDirsToWatch[i];
myWatcher.Enabl eRaisingEvents = true;

FileWatchers.Ad d(myWatcher);
}

[David]

Nicholas:

Are you sure the naming of the file system watcher is not an issue ?
It would seem to me now that I have the creation code in a loop, that
everytime the loop iterates a object gets created, but it has the same
name as the one that just got created, so doesn't that mangle the first
one ?

For instance: I create a object called myWatcher, set all of its
properties and enable it to start watching, then the loop starts over
and I create a new object called myWatcher, what has happened to the
first on that was created ?

Here is the exact message from the development environment when it hits
the line myWatcher.Enabl eRaisingEvents = true;

An unhandled exception of type 'System.IO.File NotFoundExcepti on'
occurred in system.dll

Additional information: Error reading the C:\FileWatcherT est
directory.

From this text, I would think that the directory doesn't exist, but I

know it does. I just created it.

Thanks

David