C# WPF transparent window with a border

I threw together a quick TransparencyConverter class based on this tutorial on Microsoft.com you can use for this purpose:

using System;using System.Runtime.InteropServices;using System.Windows;using System.Windows.Interop;namespace WpfApplication2{    class TransparencyConverter    {        private readonly Window _window;        public TransparencyConverter(Window window)        {            _window = window;        }        public void MakeTransparent()        {            var mainWindowPtr = new WindowInteropHelper(_window).Handle;            var mainWindowSrc = HwndSource.FromHwnd(mainWindowPtr);            if (mainWindowSrc != null)                if (mainWindowSrc.CompositionTarget != null)                    mainWindowSrc.CompositionTarget.BackgroundColor = System.Windows.Media.Color.FromArgb(0, 0, 0, 0);            var margins = new Margins            {                cxLeftWidth = 0,                cxRightWidth = Convert.ToInt32(_window.Width) * Convert.ToInt32(_window.Width),                cyTopHeight = 0,                cyBottomHeight = Convert.ToInt32(_window.Height) * Convert.ToInt32(_window.Height)            };            if (mainWindowSrc != null) DwmExtendFrameIntoClientArea(mainWindowSrc.Handle, ref margins);        }        [StructLayout(LayoutKind.Sequential)]        public struct Margins        {            public int cxLeftWidth;            public int cxRightWidth;            public int cyTopHeight;            public int cyBottomHeight;        }        [DllImport("DwmApi.dll")]        public static extern int DwmExtendFrameIntoClientArea(IntPtr hwnd, ref Margins pMarInset);    }}

Once you have this in, add the Transparent Background attribute to your XAML and subscribe to the Window_Loaded event and call the MakeTransparent method:

<Window etc etc Background="Transparent" Loaded="Window_Loaded">private void Window_Loaded(object sender, RoutedEventArgs e){    var transparencyConverter = new TransparencyConverter(this);    transparencyConverter.MakeTransparent();}

A screenshot is below:

I would first look at the (a)lpha setting in the rgb(a) color of the background color.The alpha setting sets the opacity of the object color.

Although, I notice that as I'm posting this, there is another post before mine that looks more concise and would probably be more appropriate for you.