Loading PictureBox images using OpenFileDialog

[Guest]

If I load a PictureBox image from an embedded resource within my application
it works fine but if I load the same image from a file using OpenFileDialog
(as an ImageStream or using the file name) the background color is not masked
out.

Any ideas?

 

[Herfried K. Wagner [MVP]]

If I load a PictureBox image from an embedded resource within my
application
it works fine but if I load the same image from a file using
OpenFileDialog
(as an ImageStream or using the file name) the background color is not
masked
out.

Which image format does the image have?

 

[Guest]

I have tried with a bmp image and a gif image and the problem is the same for
both formats

 

[Cor Ligthert [MVP]]

Kevin,

There seems something very special in you code. The OpenFileDialog is only
giving a string to use in the by instance image.fromstream command.

I hope this helps,

Cor

 

[Guest]

Cor,

The code I am using is as follows:

Dim ImageStream As System.IO.Stream

If openFileDialog1.ShowDialog() = DialogResult.OK Then

ImageStream = openFileDialog1.OpenFile()

If Not (ImageStream Is Nothing) Then

picImage.Image = Image.FromStream(ImageStream)

End If

End If

 

[Cor Ligthert [MVP]]

Kevin,

Maybe is yours better and did I even write the wrong method in my previous
reply.

However I use normally is. (watch typos, I typed most it in this message)

\\\
If openFileDialog1.ShowDialog() = DialogResult.OK Then
picImage.Image = Image.FromFile(openFileDialog1.FileName)
End If
////

http://msdn.microsoft.com/library/d...frlrfsystemdrawingimageclassfromfiletopic.asp

Have a look at the overloaded method as well.

I hope this helps,

Cor

 

[Herfried K. Wagner [MVP]]

I have tried with a bmp image and a gif image and the problem is the same
for
both formats

BMP doesn't support transparent backcolors at all. Use the code below to
load a transparent GIF file:

\\\
Dim o As New OpenFileDialog()
If o.ShowDialog() = DialogResult.OK Then
Me.PictureBox1.Image = Image.FromFile(o.FileName)
End If
o.Dispose()
///

 

[Guest]

We can set colors in bitmaps to transparent in VB.Net so shouldn't bmp handle
transparent backgrounds if using 32bit bitmaps? I know you are correct
because I've tried saving 32 bit bitmaps with a color transparent and it
doesn't work.

 

[Herfried K. Wagner [MVP]]

We can set colors in bitmaps to transparent in VB.Net so shouldn't bmp
handle
transparent backgrounds if using 32bit bitmaps? I know you are correct
because I've tried saving 32 bit bitmaps with a color transparent and it
doesn't work.

You can actually make the bitmap transparent in memory by calling its
'MakeTransparent' method, for example.