为什么在 Nuget 上找到的包不是最新版本？

Question

Why do I add packages such as Microsoft.AspNetCore.Http.Extensions to the .net core3.1 class library project, but only the 2.2 version can be found?

In the class library project of the same solution, the same version of these two packages cannot be found on nuget.

thanks

Answer 1

TLDR - it is at the latest version.

Visit the nuget page of Microsoft.AspNetCore.Http.Extensions here: : https://www.nuget.org/packages/Microsoft.AspNetCore.Http.Extensions/

You'll notice that the most recent version is indeed 2.2.0

Why is that? Nuget packages reference each other with requirements. So a package with a version XYZ might well require another library of STU version, with the two version numbers being vastly different. Raising the version of one, doesn't mean that there will be a need to raise the other too.

In semantic versioning the numbers (usually) just indicate the following

XYZ

X. Major version. If this changes, then there are breaking changes in the update Y. Minor version. If this changes, it is only additional functionality added, and you can update in the safety of knowing that your code won't break. Z. Patch version. This is usually just bug fixes and performance enhancements.

Answer 2

For ASP.NET Core 3 this package is no longer produced. See Migrate from ASP.NET Core 2.2 to 3.0 - Remove obsolete package references

So you don't need it for ASP.NET Core 3 and this is enough:

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

  <PropertyGroup>
    <TargetFramework>netcoreapp3.0</TargetFramework>
  </PropertyGroup>

</Project>

large number of NuGet packages aren't produced for ASP.NET Core 3.0. Such package references should be removed from your project file.

...

To see the full list of packages that are no longer produced ...

• Microsoft.AspNetCore
• Microsoft.AspNetCore.All
• Microsoft.AspNetCore.App
• Microsoft.AspNetCore.Antiforgery
• Microsoft.AspNetCore.Authentication
• Microsoft.AspNetCore.Authentication.Abstractions
• Microsoft.AspNetCore.Authentication.Cookies
• Microsoft.AspNetCore.Authentication.Core
• Microsoft.AspNetCore.Authentication.OAuth
• Microsoft.AspNetCore.Authorization.Policy
• Microsoft.AspNetCore.CookiePolicy
• Microsoft.AspNetCore.Cors
• Microsoft.AspNetCore.Diagnostics
• Microsoft.AspNetCore.Diagnostics.HealthChecks
• Microsoft.AspNetCore.HostFiltering
• Microsoft.AspNetCore.Hosting
• Microsoft.AspNetCore.Hosting.Abstractions
• Microsoft.AspNetCore.Hosting.Server.Abstractions
• Microsoft.AspNetCore.Http
• Microsoft.AspNetCore.Http.Abstractions
• Microsoft.AspNetCore.Http.Connections
• Microsoft.AspNetCore.Http.Extensions
• Microsoft.AspNetCore.HttpOverrides
• Microsoft.AspNetCore.HttpsPolicy
• Microsoft.AspNetCore.Identity
• Microsoft.AspNetCore.Localization
• Microsoft.AspNetCore.Localization.Routing
• Microsoft.AspNetCore.Mvc
• Microsoft.AspNetCore.Mvc.Abstractions
• Microsoft.AspNetCore.Mvc.Analyzers
• Microsoft.AspNetCore.Mvc.ApiExplorer
• Microsoft.AspNetCore.Mvc.Api.Analyzers
• Microsoft.AspNetCore.Mvc.Core
• Microsoft.AspNetCore.Mvc.Cors
• Microsoft.AspNetCore.Mvc.DataAnnotations
• Microsoft.AspNetCore.Mvc.Formatters.Json
• Microsoft.AspNetCore.Mvc.Formatters.Xml
• Microsoft.AspNetCore.Mvc.Localization
• Microsoft.AspNetCore.Mvc.Razor
• Microsoft.AspNetCore.Mvc.Razor.ViewCompilation
• Microsoft.AspNetCore.Mvc.RazorPages
• Microsoft.AspNetCore.Mvc.TagHelpers
• Microsoft.AspNetCore.Mvc.ViewFeatures
• Microsoft.AspNetCore.Razor
• Microsoft.AspNetCore.Razor.Runtime
• Microsoft.AspNetCore.Razor.Design
• Microsoft.AspNetCore.ResponseCaching
• Microsoft.AspNetCore.ResponseCaching.Abstractions
• Microsoft.AspNetCore.ResponseCompression
• Microsoft.AspNetCore.Rewrite
• Microsoft.AspNetCore.Routing
• Microsoft.AspNetCore.Routing.Abstractions
• Microsoft.AspNetCore.Server.HttpSys
• Microsoft.AspNetCore.Server.IIS
• Microsoft.AspNetCore.Server.IISIntegration
• Microsoft.AspNetCore.Server.Kestrel
• Microsoft.AspNetCore.Server.Kestrel.Core
• Microsoft.AspNetCore.Server.Kestrel.Https
• Microsoft.AspNetCore.Server.Kestrel.Transport.Abstractions
• Microsoft.AspNetCore.Server.Kestrel.Transport.Sockets
• Microsoft.AspNetCore.Session
• Microsoft.AspNetCore.SignalR
• Microsoft.AspNetCore.SignalR.Core
• Microsoft.AspNetCore.StaticFiles
• Microsoft.AspNetCore.WebSockets
• Microsoft.AspNetCore.WebUtilities
• Microsoft.Net.Http.Headers