<Window
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
AllowsTransparency="True" WindowStyle="None"
>
AllowsTransparency="True" WindowStyle="None" //设置窗口无边框
原文：http://blog.csdn.net/wyx100/article/details/43882457