Scaling image for printing
I'm using the following code to print an image from a PictureBox. All works great except for scaling images down if they are bigger than the print page. Is there a method I'm missing to do this?
Screenshot, large image outside of the paper bounds:
http://a.yfrog.com/img46/63/problemsh.png http://a.yfrog.com/im开发者_如何学JAVAg46/63/problemsh.png
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
AddHandler PrintDocument1.PrintPage, AddressOf OnPrintPage
With PageSetupDialog1
.Document = PrintDocument1
.PageSettings = PrintDocument1.DefaultPageSettings
If PictureEdit1.Image.Height >= PictureEdit1.Image.Width Then
PageSetupDialog1.PageSettings.Landscape = False
Else
PageSetupDialog1.PageSettings.Landscape = True
End If
End With
PrintDialog1.UseEXDialog = True
PrintDialog1.Document = PrintDocument1
If PrintDialog1.ShowDialog = Windows.Forms.DialogResult.OK Then
PrintPreviewDialog1.Document = PrintDocument1
If PrintPreviewDialog1.ShowDialog = Windows.Forms.DialogResult.OK Then
PrintDocument1.DefaultPageSettings = PageSetupDialog1.PageSettings
PrintDocument1.Print()
End If
End If
End Sub
Private Sub OnPrintPage(ByVal sender As Object, ByVal e As System.Drawing.Printing.PrintPageEventArgs)
Dim img As Image = PictureEdit1.Image
Dim sz As New SizeF(100 * img.Width / img.HorizontalResolution, 100 * img.Height / img.VerticalResolution)
Dim p As New PointF((e.PageBounds.Width - sz.Width) / 2, (e.PageBounds.Height - sz.Height) / 2)
e.Graphics.DrawImage(img, p)
End Sub
Replace:
Dim sz As New SizeF(100 * img.Width / img.HorizontalResolution, 100 * img.Height / img.VerticalResolution)
With something like this to fit the image in the page:
dim ScaleFac as integer = 100
While (ScaleFac * img.Width / img.HorizontalResolution > e.PageBounds.Width or ScaleFac * img.Height / img.VerticalResolution > e.PageBounds.Height) and ScaleFac > 2
ScaleFac -= 1
Wend
Dim sz As New SizeF(ScaleFac * img.Width / img.HorizontalResolution, ScaleFac* img.Height / img.VerticalResolution)
You could use algebra to solve for the proper scalefac, but I don't have time to test it and if you didn't understand what I'd done that would be a lot harder for you to debug. Pretty sure you'll see what I'm trying to do here from the just the code alone! Regards.
Dim img As Image = PictureEdit1.Image
e.Graphics.DrawImage(img, 0, 0,
e.PageBounds.Width, e.PageBounds.Height)
is all that you will need to solve
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