Can't delete a file

!NoItAll

I'm having a problem deleting a file. I load a TEMPORARY image in a form, show the user the image. They close the form and I attempt to delete the image but get the error that it can not be deleted because it is in use by another process. It seems to me that I'm doing everything right. Here's my code:

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If My.Computer.FileSystem.FileExists(sFileToView.sFileName) Then

        With frmImageViewer

            .LoadImages(sFileToView) = Nothing

            .ShowDialog()

            .Dispose()

            Try

                 My.Computer.FileSystem.DeleteFile(sFileToView.sFileName)

            Catch ex As Exception

                        'silently move on

            End Try

        End With

End If

in the form that shows the image this is the code

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Dim Image1 as Bitmap
 
Friend WriteOnly Property LoadImages(ByVal ImageFile As ArcResourceFileType)       
 
        Set(ByVal value)

                Image1 = Bitmap.FromFile(ImageFile.sFileName)

                picImage.Image = Image1

        End Set
 
End Property

tlhintoq

That is a known bug in Bitmap.FromFile(string FilePath)

You need to read it into a new bitmap (tempBitmap)
then clone that into a new bitmap (finalBitmap)
then dispose of the tempBitmap
then return the finalBitmap

!NoItAll

I'm still doing something wrong. See the code below - I clone it into another bitmap, then set the original to Nothing - and I still can not delete it!

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Friend WriteOnly Property LoadImages(ByVal ImageFile As ArcResourceFileType)       
 
         Set(ByVal value)

                 Dim TempImage As New Bitmap(ImageFile.sFileName)

                 Dim Image1 as Bitmap = TempImage.Clone()

                 TempImage.Dispose()    'tried it with and without this

                 TempImage = Nothing

                 picImage.Image = Image1

         End Set
 
End Property

I get exactly the same error as before - "The process cannot access the file 'C:\Documents and Settings\ddesjardins\Local Settings\Temp\europe.tif' because it is being used by another process."

Arrrrrgh - I'm going nuts over this....

tlhintoq

Quote:

I clone it into another bitmap, then set the original to Nothing

Quote:

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                  TempImage.Dispose()    'tried it with and without this

                 TempImage = Nothing

You try to dispose of it, then try to give the disposed of object a value? Garbage Collection cannot take place on an object this is still in scope and has a value.

Worst case scenario, you might want to stop reading the graphic like that and use a file stream instead. You are welcome to translate my C# code that does this.

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             Image TempImage = null;

            Image FinalImage = null;

            bool Success = false;
 
            if (ImagePath.StartsWith(".")) return FinalImage;
 
            #region Load the image from file

            if (File.Exists(ImagePath))

            {

                DateTime FailAt = DateTime.Now.AddSeconds(30);

                while (TempImage == null)

                {

                    if (DateTime.Now > FailAt) break; // Don't wait forever if the file is junk

                    FileStream fs = null;

                    try

                    {

                        fs = new FileStream(ImagePath, FileMode.Open, FileAccess.Read);

                        TempImage = Image.FromStream(fs, false);

                        Success = true;

                    }

                    catch

                    {

                    }

             }

        }

This also incorporates multiple attempts to read the file, until a time-out occurs.

Just because windows shows the file, doesn't mean its done writing. Copying and saving can take time.

!NoItAll

You are brilliant sir!
So yes - I did simply change the code to read the image as a filestream, use the FromStream in the Image class, then close the stream. Once closed there was no other contention for the file.
It appears the FromFile method in the Image class is not so good - it holds the file open with no explicit way to close it. That seems like a potential memory leak to me!

Final working code:

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Dim fs As New System.IO.FileStream(sFirstImageFile.sFileName, IO.FileMode.Open, IO.FileAccess.Read)

picLeftImage.Image = Image.FromStream(fs, False)

fs.Close()

I'm not bothering with the error checking because I test the file before calling this. Yes - it would be better to make it sensitive to potential errors, but the purpose of this section of code is very limited...

Can't delete a file

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