chore: add Object2BooleanReConverter.

src/Net_40/HandyControl_Net_40/Themes/Theme.xaml

@@ -17,6 +17,7 @@
 	<converter:TreeViewItemMarginConverter x:Key="TreeViewItemMarginConverter" />
 	<converter:Color2HexStringConverter x:Key="Color2HexStringConverter" />
 	<converter:Object2BooleanConverter x:Key="Object2BooleanConverter" />
+	<converter:Object2BooleanReConverter x:Key="Object2BooleanReConverter" />
 	<converter:Boolean2StringConverter x:Key="Boolean2StringConverter" />
 	<converter:Int2StringConverter x:Key="Int2StringConverter" />
 	<converter:BorderClipConverter x:Key="BorderClipConverter" />

src/Shared/HandyControl_Shared/HandyControl_Shared.projitems

@@ -97,6 +97,7 @@
     <Compile Include="$(MSBuildThisFileDirectory)Interactivity\EventToCommand.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Interactivity\IEventArgsConverter.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Interactivity\MouseDragElementBehaviorEx.cs" />
+    <Compile Include="$(MSBuildThisFileDirectory)Tools\Converter\Object2BooleanReConverter.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Tools\Helper\FullScreenHelper.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Controls\Window\GlowWindow.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Data\EnumItem.cs" />

src/Shared/HandyControl_Shared/Themes/Basic/Converters.xaml

@@ -13,6 +13,7 @@
     <converter:TreeViewItemMarginConverter x:Key="TreeViewItemMarginConverter"/>
     <converter:Color2HexStringConverter x:Key="Color2HexStringConverter"/>
     <converter:Object2BooleanConverter x:Key="Object2BooleanConverter"/>
+    <converter:Object2BooleanReConverter x:Key="Object2BooleanReConverter" />
     <converter:Boolean2StringConverter x:Key="Boolean2StringConverter"/>
     <converter:Int2StringConverter x:Key="Int2StringConverter"/>
     <converter:BorderClipConverter x:Key="BorderClipConverter"/>

src/Shared/HandyControl_Shared/Themes/Theme.xaml

@@ -17,6 +17,7 @@
 	<converter:TreeViewItemMarginConverter x:Key="TreeViewItemMarginConverter" />
 	<converter:Color2HexStringConverter x:Key="Color2HexStringConverter" />
 	<converter:Object2BooleanConverter x:Key="Object2BooleanConverter" />
+	<converter:Object2BooleanReConverter x:Key="Object2BooleanReConverter" />
 	<converter:Boolean2StringConverter x:Key="Boolean2StringConverter" />
 	<converter:Int2StringConverter x:Key="Int2StringConverter" />
 	<converter:BorderClipConverter x:Key="BorderClipConverter" />

src/Shared/HandyControl_Shared/Tools/Converter/Object2BooleanConverter.cs

@@ -6,7 +6,7 @@ namespace HandyControl.Tools.Converter;
 
 public class Object2BooleanConverter : IValueConverter
 {
-    public object Convert(object value, Type targetType, object parameter, CultureInfo culture) => !(value is null);
+    public object Convert(object value, Type targetType, object parameter, CultureInfo culture) => value is not null;
 
     public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
     {

src/Shared/HandyControl_Shared/Tools/Converter/Object2BooleanReConverter.cs

@@ -0,0 +1,15 @@
+using System;
+using System.Globalization;
+using System.Windows.Data;
+
+namespace HandyControl.Tools.Converter;
+
+public class Object2BooleanReConverter : IValueConverter
+{
+    public object Convert(object value, Type targetType, object parameter, CultureInfo culture) => value is null;
+
+    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
+    {
+        throw new NotSupportedException();
+    }
+}