completed extend-controls docs

doc/source/handycontrol/extend_controls/blurWindow/index.md

@@ -0,0 +1,44 @@
+---
+title: BlurWindow 背景模糊窗口
+---
+
+背景模糊窗口可用于增强UI效果，但是会牺牲部分性能.
+
+```cs
+public class BlurWindow : Window
+```
+
+{% note warning %}
+操作系统支持范围：win10 10240 ~ win10 18362
+{% endnote %}
+
+{% note warning %}
+重写资源 `BlurGradientValue` 可自定义模糊颜色
+{% endnote %}
+
+# 案例
+
+```xml
+<system:UInt32 x:Key="BlurGradientValue">0x99FFFFFF</system:UInt32>
+```
+
+```xml
+<hc:BlurWindow x:Class="HandyControlDemo.Window.BlurWindow"
+               xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+               xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+               xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+               xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+               xmlns:hc="https://handyorg.github.io/handycontrol"
+               xmlns:langs="clr-namespace:HandyControlDemo.Properties.Langs"
+               xmlns:ex="clr-namespace:HandyControlDemo.Tools.Extension"
+               mc:Ignorable="d"
+               Style="{StaticResource WindowBlur}"
+               WindowStartupLocation="CenterScreen"
+               Title="{ex:Lang Key={x:Static langs:LangKeys.Title}}"
+               Height="450" 
+               Width="800" 
+               Icon="/HandyControlDemo;component/Resources/Img/icon.ico">
+</hc:BlurWindow>
+```
+
+![BlurWindow](https://raw.githubusercontent.com/HandyOrg/HandyOrgResource/master/HandyControl/Resources/BlurWindow.png)