C#类库打包支持多个版本的类库

修改csproj

<Project Sdk="Microsoft.NET.Sdk"><PropertyGroup><TargetFrameworks>netcoreapp3.1;net5.0;net6.0;net7.0;net8.0</TargetFrameworks><PackageId>xxxx</PackageId><Version>1.0.0</Version><Authors>wjl</Authors><Company>公司</Company><Product>产品名称</Product><Title>标题</Title><Description>简介</Description><PackageTags>tag标签多个用;分割</PackageTags><!--保留注释--><GenerateDocumentationFile>true</GenerateDocumentationFile></PropertyGroup><ItemGroup><FrameworkReference Include="Microsoft.AspNetCore.App"/></ItemGroup>
</Project>

参考

https://learn.microsoft.com/zh-cn/dotnet/standard/frameworks