WPF，创建用户控件
创建了一个继承自UserControl的用户控件，然后手动改成了继承自Window。如下：
后台：
public partial class MyWindow : Window
{
public MyWindow()
{
InitializeComponent();
}
....
....
}
<Window x:Class="WPF熊俊.MyWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
mc:Ignorable="d"
d:DesignHeight="300" d:DesignWidth="300">
....
....
</Window>
