cad.net WPF的MarkupExtension接口引用问题,System.Xaml.dll的引用问题

<Project Sdk="Microsoft.NET.Sdk">

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        <OutputPath>..\..\K01.惊惊连盒\JnFox</OutputPath>
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    <PropertyGroup Condition="‘$(Configuration)|$(TargetFramework)|$(Platform)‘==‘Debug|net35|AnyCPU‘">
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    <ItemGroup Condition="‘$(TargetFramework)‘ == ‘net35‘">
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        <!--net环境加载特定的dll-->
        <Reference Include="System.Xaml">
            <HintPath>C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.0\System.Xaml.dll</HintPath>
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        <!--net环境加载特定的dll-->
        <Reference Include="System.Xaml">
            <HintPath>C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.5\System.Xaml.dll</HintPath>
        </Reference>

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            <Version>4.0.0</Version>
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        <Reference Include="mscorlib.dll" />
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    <ItemGroup>
        <Reference Include="PresentationCore" />
        <Reference Include="PresentationFramework" />
        <Reference Include="System.Xml" />
        <Reference Include="WindowsBase" />
        <Reference Include="PresentationFramework" />
        <Reference Include="System.Xml" />
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