VB.net opening a bitmap and checking to see if it exists first

[sitko]

Hi,

I've created a program that opens a bit map and scans the pixels to count up the non-white pixels.

I put the initial open function inside of a try statement, but it fails to hit an error if the file I input doesn't exist. Also, this is a console app, not a GUI one. All the file checking I saw online only worked with the OpenFileDialog.

Here is the snipet of code:

Dim a As String
 
        For each a in args
            If Prev = "-input" then 
                InpBmp = a
            End If
              'I removed some unnecessary code here.
            Prev = a
        Next
 
        Try
 
            BitMap_Trim(InpBmp) 'this sub creates a bitmap called cropped.bmp
            b = New Bitmap(AppDomain.CurrentDomain.BaseDirectory & "cropped.bmp")
 
        Catch ex As Exception
            Console.WriteLine("Usage: Bitmap_Area_Calc.exe -input <bitmap name>.bmp -hor <number wide>" & Chr(10))
            Console.WriteLine(" [or -vert <number high>] -step <subarea to calc total>")
            Exit Sub
        End Try
 

Any suggestions as to what I'd need to add to return an error when the file that is opened, doesn't exist?

Thanks,
Sitko.

[Killer42]

I'd recommend using the FileSystemObject. It can easily tell you whether a specified file exists.