Public Class ViewerBorderPadding 

Dim instance As ViewerBorderPadding

public class ViewerBorderPadding 

public ref class ViewerBorderPadding 

Public Sub ViewerBorderPaddingExample(ByVal viewer As RasterImageViewer)
   If (viewer.IsImageAvailable) Then
      AddHandler viewer.BorderPadding.Changed, AddressOf BorderPadding_Changed
      viewer.BorderPadding.All = 0
      Dim viewerWidth As Integer = viewer.Right - viewer.Left
      Dim viewerHeight As Integer = viewer.Bottom - viewer.Top
      Dim imageWidth As Integer = viewer.Image.Width
      Dim imageHeight As Integer = viewer.Image.Height

      If (imageWidth < viewerWidth) Then
         viewer.BorderPadding.Left = (viewerWidth - imageWidth) \ 2
         viewer.BorderPadding.Right = 0
      End If

      If (imageHeight < viewerHeight) Then
         viewer.BorderPadding.Top = (viewerHeight - imageHeight) \ 2
         viewer.BorderPadding.Bottom = 0
      End If
      RemoveHandler viewer.BorderPadding.Changed, AddressOf BorderPadding_Changed
   End If
End Sub

Private Sub BorderPadding_Changed(ByVal sender As Object, ByVal e As EventArgs)
   Console.WriteLine("BorderPadding Changed")
End Sub

public void ViewerBorderPaddingExample(RasterImageViewer viewer)
{
   if(viewer.IsImageAvailable)
   {
      viewer.BorderPadding.Changed += new EventHandler(BorderPadding_Changed);
      viewer.BorderPadding.All = 0;
      int viewerWidth = viewer.Right - viewer.Left;
      int viewerHeight = viewer.Bottom - viewer.Top;
      int imageWidth = viewer.Image.Width;
      int imageHeight = viewer.Image.Height;

      if(imageWidth < viewerWidth)
      {
         viewer.BorderPadding.Left = (viewerWidth - imageWidth) / 2;
         viewer.BorderPadding.Right = 0;
      }

      if(imageHeight < viewerHeight)
      {
         viewer.BorderPadding.Top = (viewerHeight - imageHeight) / 2;
         viewer.BorderPadding.Bottom = 0;
      }

      viewer.BorderPadding.Changed -= new EventHandler(BorderPadding_Changed);
   }
}

private void BorderPadding_Changed(System.Object sender, EventArgs e)
{
   Console.WriteLine("BorderPadding Changed");
}