多年前在Windows下，我正在一个最初由我不认识的其他人创建的旧项目上运行dotnet build命令，但是在我的Linux Ubuntu 16.04笔记本电脑上，它给了我错误：
/home/stephane/programs/dotnet-sdk-2.2.204-linux-x64/sdk/2.2.204/Microsoft.Common.CurrentVersion.targets(1183,5): error MSB3644: The reference assemblies for framework ".NETFramework,Version=v3.5" were not found.
我昨天下载并安装了dotnet存档的dotnet-sdk-2.2.204-linux-x64 SDK，配置信息为：
$ dotnet --info
.NET Core SDK (reflecting any global.json):
Version: 2.2.204
Commit: 8757db13ec
Runtime Environment:
OS Name: ubuntu
OS Version: 16.04
OS Platform: Linux
RID: ubuntu.16.04-x64
Base Path: /home/stephane/programs/dotnet-sdk-2.2.204-linux-x64/sdk/2.2.204/
Host (useful for support):
Version: 2.2.5
Commit: 0a3c9209c0
.NET Core SDKs installed:
2.2.204 [/home/stephane/programs/dotnet-sdk-2.2.204-linux-x64/sdk]
.NET Core runtimes installed:
Microsoft.AspNetCore.All 2.2.5 [/home/stephane/programs/dotnet-sdk-2.2.204-linux-x64/shared/Microsoft.AspNetCore.All]
Microsoft.AspNetCore.App 2.2.5 [/home/stephane/programs/dotnet-sdk-2.2.204-linux-x64/shared/Microsoft.AspNetCore.App]
Microsoft.NETCore.App 2.2.5 [/home/stephane/programs/dotnet-sdk-2.2.204-linux-x64/shared/Microsoft.NETCore.App]
To install additional .NET Core runtimes or SDKs:
https://aka.ms/dotnet-download
.csproj文件包含：
<Project ToolsVersion="3.5" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
<PropertyGroup>
<ProjectGuid>{1F89C6A7-BCC7-4B9A-AF06-4BA515541489}</ProjectGuid>
<Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
<Platform Condition=" '$(Platform)' == '' ">x86</Platform>
<OutputType>WinExe</OutputType>
<RootNamespace>RoseauWin</RootNamespace>
<AssemblyName>RoseauWin</AssemblyName>
<TargetFrameworkVersion>v3.5</TargetFrameworkVersion>
<AppDesignerFolder>Properties</AppDesignerFolder>
</PropertyGroup>
<PropertyGroup Condition=" '$(Platform)' == 'x86' ">
<PlatformTarget>x86</PlatformTarget>
</PropertyGroup>
<PropertyGroup Condition=" '$(Configuration)' == 'Debug' ">
<OutputPath>bin\Debug\</OutputPath>
<DebugSymbols>True</DebugSymbols>
<DebugType>Full</DebugType>
<Optimize>False</Optimize>
<CheckForOverflowUnderflow>True</CheckForOverflowUnderflow>
<DefineConstants>DEBUG;TRACE</DefineConstants>
</PropertyGroup>
<PropertyGroup Condition=" '$(Configuration)' == 'Release' ">
<OutputPath>bin\Release\</OutputPath>
<DebugSymbols>False</DebugSymbols>
<DebugType>None</DebugType>
<Optimize>True</Optimize>
<CheckForOverflowUnderflow>False</CheckForOverflowUnderflow>
<DefineConstants>TRACE</DefineConstants>
</PropertyGroup>
<Import Project="$(MSBuildBinPath)\Microsoft.CSharp.targets" />
<ItemGroup>
<Reference Include="Sanford.Multimedia">
<HintPath>..\Sanford.Multimedia.Midi\bin\Debug\Sanford.Multimedia.dll</HintPath>
</Reference>
<Reference Include="System" />
<Reference Include="System.Configuration" />
<Reference Include="System.Core">
<RequiredTargetFramework>3.5</RequiredTargetFramework>
</Reference>
<Reference Include="System.Core">
<RequiredTargetFramework>3.5</RequiredTargetFramework>
</Reference>
<Reference Include="System.Data" />
<Reference Include="System.Data.DataSetExtensions">
<RequiredTargetFramework>3.5</RequiredTargetFramework>
</Reference>
<Reference Include="System.Drawing" />
<Reference Include="System.Windows.Forms" />
<Reference Include="System.Xml" />
<Reference Include="System.Xml.Linq">
<RequiredTargetFramework>3.5</RequiredTargetFramework>
</Reference>
</ItemGroup>
<ItemGroup>
<Compile Include="MainForm.cs" />
<Compile Include="MainForm.Designer.cs">
<DependentUpon>MainForm.cs</DependentUpon>
</Compile>
<Compile Include="Program.cs" />
<Compile Include="Properties\AssemblyInfo.cs" />
<EmbeddedResource Include="MainForm.resx">
<DependentUpon>MainForm.cs</DependentUpon>
</EmbeddedResource>
</ItemGroup>
<ItemGroup>
<ProjectReference Include="..\Roseau.ComponentModel\Roseau.ComponentModel.csproj">
<Project>{28F134E7-F044-4153-A8AE-0C18E6351635}</Project>
<Name>Roseau.ComponentModel</Name>
</ProjectReference>
<ProjectReference Include="..\Roseau.Music.Generators\Roseau.Music.Generators.csproj">
<Project>{DBE17471-321A-400D-97A9-ADCEBFE960EA}</Project>
<Name>Roseau.Music.Generators</Name>
</ProjectReference>
<ProjectReference Include="..\Roseau.Music.Midi\Roseau.Music.Midi.csproj">
<Project>{FF7B26FF-AB13-4FCC-AC85-9FD04C2D0F1A}</Project>
<Name>Roseau.Music.Midi</Name>
</ProjectReference>
<ProjectReference Include="..\Roseau.Music\Roseau.Music.csproj">
<Project>{9A4CF19C-B0A7-4D74-8B01-C479FE8C3019}</Project>
<Name>Roseau.Music</Name>
</ProjectReference>
<ProjectReference Include="..\Roseau.Probability\Roseau.Probability.csproj">
<Project>{CA266A83-CB09-4A37-9160-0E67B7035C9C}</Project>
<Name>Roseau.Probability</Name>
</ProjectReference>
<ProjectReference Include="..\Roseau.Windows.Forms\Roseau.Windows.Forms.csproj">
<Project>{CCAC8FF9-E2BD-4B76-B479-72D91D1170BD}</Project>
<Name>Roseau.Windows.Forms</Name>
</ProjectReference>
<ProjectReference Include="..\Sanford.Multimedia.Midi\Sanford.Multimedia.Midi.csproj">
<Project>{4269C72A-8D3A-4737-8F89-72EAA33EA9E1}</Project>
<Name>Sanford.Multimedia.Midi</Name>
</ProjectReference>
</ItemGroup>
</Project>
上面的文件是构建文件吗？等价于Maven Java应用程序中的pom.xml文件？
我以前从未接触过.Net应用。
ToolsVersion="3.5"和<TargetFrameworkVersion>v3.5</TargetFrameworkVersion>是什么？
我可以编辑此文件吗？我可以更改哪个版本？
我已经看过这个page，希望我不必为了构建它而学到太多知识。毕竟，我正在使用Java和Typescript从头开始重写该应用程序。