blocks|key|2908056|text|取决于版本。根据下面的描述，旧的System.Net.Http包(+2.0包)是为了支持Microsoft.Http.Net而被弃用的遗留包：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|2908057|2908058|传统包，System.Net.Http现在包含在'Microsoft.Net.Http‘包中。|blockquote|2908059|2908060|2908061|它们的存在是为了在以前的.NET版本和可移植类库中提供HttpClient。在这种情况下，您应该使用Microsoft.Net.Http。|2908062|由于您使用的是.NET核心，因此您应该使用最新的System.Net.Http包(例如，4.3.3)。|2908063|已为csproj更新|2908064|从.NET标准2.0开始，已经包含了System.Net.HttpClient包，并且在您针对netstandard2.0时可以使用它。如果出于某种原因，您仍然希望在完整的.NET和.NET核心中引用它，您可以将以下内容添加到您的csproj文件中：|BOLD|2908065|<ItemGroup+Condition="+'$(TargetFramework)'+==+'net461'+">
++++
++++<Reference+Include="System.Net.Http"+/>
</ItemGroup>
<ItemGroup+Condition="+'$(TargetFramework)'+==+'netstandard2.0'+">
++++
++++<PackageReference+Include="System.Net.Http"+Version="4.3.3"+/>
</ItemGroup>|code-block|syntax|javascript|2908066|2908067|如果使用的是project.json，则为|2908068|如果您的project.json同时针对完整的.NET和.NET核心，则必须将System.Net.Http程序集添加到frameworkAssemblies元素。例如：|2908069|"frameworks":+{
++"net451":+{
++++"frameworkAssemblies":+{
++++++"System.Net.Http":+"4.0.0.0"+//+HttpClient+for+full+.NET
++++}
++},
++"netstandard1.3":+{
++++"dependencies":+{
++++++"System.Net.Http":+"4.1.0",+//+HttpClient+for+.NET+Core
++++}
++}
}|2908070|entityMap|0|LINK|mutability|MUTABLE|url|https://www.nuget.org/packages/System.Net.Http/2.0.20710|1|https://www.nuget.org/packages/Microsoft.Net.Http|2|https://www.nuget.org/packages/System.Net.Http^0|G|F|18|I|Y|3|0|18|I|1|0|0|0|0|0|R|A|1E|I|0|O|F|O|F|2|0|0|0|3H|I|L|1B|E|0|0|0|0|I|0|0|2D|13|F|1O|J|0|0^^$0|@$1|2|3|4|5|6|7|1I|8|@$9|1J|A|1K|B|C]|$9|1L|A|1M|B|C]]|D|@$9|1N|A|1O|1|1P]|$9|1Q|A|1R|1|1S]]|E|$]]|$1|F|3|-4|5|6|7|1T|8|@]|D|@]|E|$]]|$1|G|3|H|5|I|7|1U|8|@]|D|@]|E|$]]|$1|J|3|-4|5|6|7|1V|8|@]|D|@]|E|$]]|$1|K|3|-4|5|6|7|1W|8|@]|D|@]|E|$]]|$1|L|3|M|5|6|7|1X|8|@$9|1Y|A|1Z|B|C]|$9|20|A|21|B|C]]|D|@]|E|$]]|$1|N|3|O|5|6|7|22|8|@$9|23|A|24|B|C]]|D|@$9|25|A|26|1|27]]|E|$]]|$1|P|3|Q|5|6|7|28|8|@]|D|@]|E|$]]|$1|R|3|S|5|6|7|29|8|@$9|2A|A|2B|B|T]|$9|2C|A|2D|B|C]|$9|2E|A|2F|B|C]]|D|@]|E|$]]|$1|U|3|V|5|W|7|2G|8|@]|D|@]|E|$X|Y]]|$1|Z|3|-4|5|6|7|2H|8|@]|D|@]|E|$]]|$1|10|3|11|5|6|7|2I|8|@$9|2J|A|2K|B|T]]|D|@]|E|$]]|$1|12|3|13|5|6|7|2L|8|@$9|2M|A|2N|B|T]|$9|2O|A|2P|B|C]|$9|2Q|A|2R|B|C]]|D|@]|E|$]]|$1|14|3|15|5|W|7|2S|8|@]|D|@]|E|$X|Y]]|$1|16|3|-4|5|6|7|2T|8|@]|D|@]|E|$]]]|17|$18|$5|19|1A|1B|E|$1C|1D]]|1E|$5|19|1A|1B|E|$1C|1F]]|1G|$5|19|1A|1B|E|$1C|1H]]]]

Depends on the version. The old <code>System.Net.Http</code> packages (the <a href="https://www.nuget.org/packages/System.Net.Http/2.0.20710" rel="nofollow noreferrer">2.0</a> ones) are legacy packages which are deprecated in favor of <a href="https://www.nuget.org/packages/Microsoft.Net.Http" rel="nofollow noreferrer"><code>Microsoft.Http.Net</code></a> according to the description:
<blockquote>
Legacy package, System.Net.Http is now included in the
'Microsoft.Net.Http' package.
</blockquote>
They exist to provide the <code>HttpClient</code> in previous .NET versions and Portable Class libraries. You should use <code>Microsoft.Net.Http</code> in that case.
Since you're using .NET Core, you should use the latest <a href="https://www.nuget.org/packages/System.Net.Http" rel="nofollow noreferrer"><code>System.Net.Http</code></a> package (eg. 4.3.3).
Updated for csproj
As of .NET Standard 2.0, the <code>System.Net.HttpClient</code> package is already included and available when you target <code>netstandard2.0</code>. If, for some reason, you still want to reference it for both full .NET and .NET Core, you can add this to your csproj file:
<pre class="lang-xml prettyprint-override"><code>&lt;ItemGroup Condition=&quot; '$(TargetFramework)' == 'net461' &quot;&gt;
 &lt;!-- // HttpClient for full .NET --&gt;
 &lt;Reference Include=&quot;System.Net.Http&quot; /&gt;
&lt;/ItemGroup&gt;
&lt;ItemGroup Condition=&quot; '$(TargetFramework)' == 'netstandard2.0' &quot;&gt;
 &lt;!-- // HttpClient for .NET Core --&gt;
 &lt;PackageReference Include=&quot;System.Net.Http&quot; Version=&quot;4.3.3&quot; /&gt;
&lt;/ItemGroup&gt;
</code></pre>
<hr>
If you're using project.json
If your project.json targets both full .NET and .NET Core, you have to add the <code>System.Net.Http</code> assembly to the <code>frameworkAssemblies</code> element. For example:
<pre class="lang-js prettyprint-override"><code>&quot;frameworks&quot;: {
 &quot;net451&quot;: {
 &quot;frameworkAssemblies&quot;: {
 &quot;System.Net.Http&quot;: &quot;4.0.0.0&quot; // HttpClient for full .NET
 }
 },
 &quot;netstandard1.3&quot;: {
 &quot;dependencies&quot;: {
 &quot;System.Net.Http&quot;: &quot;4.1.0&quot;, // HttpClient for .NET Core
 }
 }
}
</code></pre>

blocks|key|133816|text|Microsoft.Net.Http需要额外的Microsoft.Bcl依赖项。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|133817|因此，如果您只针对.NET框架或.NET核心，则可以使用System.Net.Http。否则，Microsoft.Net.Http将是更好的选择，因为它可能是下一代。|133818|entityMap^0|0|I|N|D|0|S|F|1B|I|0^^$0|@$1|2|3|4|5|6|7|J|8|@$9|K|A|L|B|C]|$9|M|A|N|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|O|8|@$9|P|A|Q|B|C]|$9|R|A|S|B|C]]|D|@]|E|$]]|$1|H|3|-4|5|6|7|T|8|@]|D|@]|E|$]]]|I|$]]

<code>Microsoft.Net.Http</code> requires additional <code>Microsoft.Bcl</code> dependencies.

For that, if you are only targeted .NET Framework or .NET Core, <code>System.Net.Http</code> is good to go. Otherwise, <code>Microsoft.Net.Http</code> would be better choice as it could be the next generation.

blocks|key|2908213|text|对于任何对此感兴趣的人，请参阅Immo+Landwerth+(微软.NET上的项目经理)+tweeted：|type|unstyled|depth|inlineStyleRanges|offset|length|style|BOLD|entityRanges|data|2908214|"HttpClient最初是一个NuGet包(带外)，在4.5中也被添加到了.NET框架中(在盒子里)。|2908215|在.NET核心/+.NET标准中，我们最初试图将.NET平台建模为一组包，其中在盒内还是带外不再重要。然而，这比我们预期的更加混乱和复杂。|2908216|因此，我们在很大程度上放弃了使用核心/标准2.0将.NET平台建模为NuGet图的想法。|2908217|一般的答案是：|2908218|使用.NET+Core2.0和.NET标准2.0，您根本不需要引用SystemNetHttpClient+NuGet包。不过，它可能会从1.x依赖项中拉出来。|2908219|.NET框架也是如此:如果你的目标是4.5或更高版本，你通常应该使用内置版本而不是NuGet包。同样，您可能最终会在PCL+1.x和.NET依赖项中使用它，但是直接针对.NET框架编写的代码不应该使用它。|2908220|2908221|遗留包的预期模型是:如果您使用来自.NET框架4.5%2B，.NET核心2%2B，.NET标准2%2B的包，包只转发到平台提供的实现，而不是带来它自己的版本。|2908222|然而，这并不是在所有情况下都会发生的事情:+HTTP+Client包将(部分)替换.NET框架上的内置组件，后者碰巧对一些客户有效，而对另一些客户无效。|2908223|最重要的是，我们有.NET框架常见的绑定问题，所以只有在添加绑定重定向的情况下，这才能很好地工作。耶！|2908224|因此，作为一个库作者，我的建议是避免依赖这个包，而更喜欢.NET+Framework4.5、.NET+Core2.0和.NET标准2.0中的内置版本。“|2908225|https://twitter.com/terrajobst/status/997262020108926976|2908226|entityMap|0|LINK|mutability|MUTABLE|url|1^0|F|E|19|7|0|0|0|0|0|0|0|0|0|0|0|0|0|0|1K|1|0^^$0|@$1|2|3|4|5|6|7|1A|8|@$9|1B|A|1C|B|C]]|D|@$9|1D|A|1E|1|1F]]|E|$]]|$1|F|3|G|5|6|7|1G|8|@]|D|@]|E|$]]|$1|H|3|I|5|6|7|1H|8|@]|D|@]|E|$]]|$1|J|3|K|5|6|7|1I|8|@]|D|@]|E|$]]|$1|L|3|M|5|6|7|1J|8|@]|D|@]|E|$]]|$1|N|3|O|5|6|7|1K|8|@]|D|@]|E|$]]|$1|P|3|Q|5|6|7|1L|8|@]|D|@]|E|$]]|$1|R|3|-4|5|6|7|1M|8|@]|D|@]|E|$]]|$1|S|3|T|5|6|7|1N|8|@]|D|@]|E|$]]|$1|U|3|V|5|6|7|1O|8|@]|D|@]|E|$]]|$1|W|3|X|5|6|7|1P|8|@]|D|@]|E|$]]|$1|Y|3|Z|5|6|7|1Q|8|@]|D|@]|E|$]]|$1|10|3|11|5|6|7|1R|8|@]|D|@$9|1S|A|1T|1|1U]]|E|$]]|$1|12|3|-4|5|6|7|1V|8|@]|D|@]|E|$]]]|13|$14|$5|15|16|17|E|$18|11]]|19|$5|15|16|17|E|$18|11]]]]

For anyone interested in more background to this, Immo Landwerth (Program manager on .NET at Microsoft) <a href="https://twitter.com/terrajobst/status/997262020108926976" rel="noreferrer">tweeted</a> about this:

"HttpClient started out as a NuGet package (out-of-band) and was added to the .NET Framework in 4.5 as well (in-box).

With .NET Core/.NET Standard we originally tried to model the .NET platform as a set of packages where being in-box vs. out-of-band no longer mattered. However, this was messier and more complicated than we anticipated.

As a result, we largely abandoned the idea of modeling the .NET platform as a NuGet graph with Core/Standard 2.0.

The general answer is:

With .NET Core 2.0 and .NET Standard 2.0 you shouldn't need to reference the SystemNetHttpClient NuGet package at all. It might get pulled from 1.x dependencies though.

Same goes for .NET Framework: if you target 4.5 and up, you should generally use the in-box version instead of the NuGet package. Again, you might end up pulling it in for .NET Standard 1.x and PCL dependencies, but code written directly against .NET Framework shouldn't use it.

So why does the package still exist/why do we still update it? Simply because we want to make existing code work that took a dependency on it. However, as you discovered that isn't smooth sailing on .NET Framework.

The intended model for the legacy package is: if you consume the package from .NET Framework 4.5+, .NET Core 2+, .NET Standard 2+ the package only forwards to the platform provided implementation as opposed to bring it's own version.

That's not what actually happens in all cases though: the HTTP Client package will (partially) replace in-box components on .NET Framework which happen to work for some customers and fails for others. Thus, we cannot easily fix the issue now.

On top of that we have the usual binding issues with the .NET Framework so this only really works well if you add binding redirects. Yay!

So, as a library author my recommendation is to avoid taking a dependency on this package and prefer the in-box versions in .NET Framework 4.5, .NET Core 2.0 and .NET Standard 2.0."

<a href="https://twitter.com/terrajobst/status/997262020108926976" rel="noreferrer">https://twitter.com/terrajobst/status/997262020108926976</a>

I am using ASP.NET Core. I want to use <code>HttpClient</code> but I noticed that there are two NuGet packages being offered. Which one do I use?

<ul>
<li><a href="https://www.nuget.org/packages/System.Net.Http" rel="noreferrer">System.Net.Http</a></li>
<li><a href="https://www.nuget.org/packages/Microsoft.Net.Http" rel="noreferrer">Microsoft.Net.Http</a></li>
</ul>

System.Net.Http vs Microsoft.Net.Http

我使用的是ASP.NET内核。我想使用HttpClient，但我注意到提供了两个NuGet包。我该用哪一个？

问System.Net.Http vs Microsoft.Net.Http
EN

社区

活动

资源

关于

腾讯云开发者

热门产品

热门推荐

更多推荐

问System.Net.Http vs Microsoft.Net.HttpEN

社区

活动

资源

关于

腾讯云开发者

热门产品

热门推荐

更多推荐

问System.Net.Http vs Microsoft.Net.Http
EN