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c# - save an image from ink canvas

I am trying to save an image from ink canvas however it does not create any file after saving, this is my code

RenderTargetBitmap rtb = new RenderTargetBitmap(
    (int)canvas.Width, (int)canvas.Height, 0, 0, PixelFormats.Default);

rtb.Render(this.canvas);

JpegBitmapEncoder encoder = new JpegBitmapEncoder();

encoder.Frames.Add(BitmapFrame.Create(rtb));

using(var file = new FileStream(@"C:est.jpg", FileMode.Create))
{
   encoder.Save(file);
}

however it does not create any file even when I change the directory. No exceptions is invoked and no errors are shown. The code just ran normally without any problem but the file meant to be generated is not there.

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by (71.8m points)

try using a Save File Dialog

Here is an example code i used in my class "add signature" in vb.net

upon button click a savefile dialog box will appear, after putting a file name and pressing save, it will be save as a png image(i used pngBitmap Encoder)

This has same format with what you are using but with a save file dialog added.

btw. WPFControl.Inkcanvas1 is my inkcanvas

'buttonSaveAsClick


   'open save file dialog box
    Dim sfd As New SaveFileDialog()
    sfd.Filter = "Png Files(*.png)|*.png"

    'save file as png (render bitmap and convert/save to png)
    Dim result As Nullable(Of Boolean) = sfd.ShowDialog()
    Dim fileName As String = ""

    If result = True Then
        fileName = sfd.FileName

        Dim size As Size = New Point(750, 400) '= WPFControl.InkCanvas1.RenderSize 
        Console.WriteLine(WPFControl.InkCanvas1.RenderSize)
        Dim rtb As New RenderTargetBitmap(CInt(size.Width), CInt(size.Height), 96, 96, Windows.Media.PixelFormats.Pbgra32)
        rtb.Render(WPFControl.InkCanvas1)
        Dim png As New PngBitmapEncoder()
        png.Frames.Add(BitmapFrame.Create(rtb))
        If String.IsNullOrEmpty(fileName) = True Then
            MsgBox("Please Enter a File Name", MsgBoxStyle.Exclamation, "File Name required!")
            Exit Sub

        Else
            Console.WriteLine(sfd.FileName)
            Console.WriteLine(convertImage.ConvertImageFiletoBytes(sfd.FileName))
        End If


        Using stm As Stream = File.Create(fileName)
            png.Save(stm)

        End Using
    End If

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