docs: 完善文档

docs/WechatTenpayV3/Advanced_IHttpClientFactory.md

@@ -7,44 +7,62 @@
 > [《Microsoft Docs - 使用 IHttpClientFactory 实现复原 HTTP 请求》](https://docs.microsoft.com/zh-cn/dotnet/architecture/microservices/implement-resilient-applications/use-httpclientfactory-to-implement-resilient-http-requests)
 >
 > [《Microsoft Docs - 在 ASP.NET Core 中使用 IHttpClientFactory 发出 HTTP 请求》](https://docs.microsoft.com/zh-cn/aspnet/core/fundamentals/http-requests#httpclient-and-lifetime-management)
+>
+> [《Microsoft Docs - .NET Core 2.1 的新增功能：套接字改进》](https://docs.microsoft.com/zh-CN/dotnet/core/whats-new/dotnet-core-2-1#sockets-improvements)
 
-你可以在构造得到 `WechatTenpayClient` 对象后：
+当你的项目是运行在 ASP.NET Core 2.1 或更高版本的平台时，CLR 已经提供了全新的底层套接字实现，无需你手动干预 `HttpClient` 的生命周期。
+
+如果你想手动管理 `HttpClient`，那么可以参考下面基于 DI/IoC 的代码实现：
 
 ```csharp
-client.Configure(settings =>
+using Flurl.Http;
-{
+using Flurl.Http.Configuration;
-    settings.HttpClientFactory = HttpClientFactory; // 赋值为依赖注入的 `IHttpClientFactory` 对象
-});
-```
-
-下面给出一个使用了依赖注入的完整例子：
-
-```csharp
-using System.Net.Http;
-using Microsoft.Extensions.Http;
 using Microsoft.Extensions.Options;
 using SKIT.FlurlHttpClient.Wechat.TenpayV3;
 using SKIT.FlurlHttpClient.Wechat.TenpayV3.Models;
 
-public class MyWechatClientFactory
+public class WechatTenpayClientFactory
 {
-    private readonly IHttpClientFactory _httpClientFactory;
+    internal class DelegatingFlurlClientFactory : IFlurlClientFactory
+    {
+        private readonly System.Net.Http.IHttpClientFactory _httpClientFactory;
+
+        public DelegatingFlurlClientFactory(System.Net.Http.IHttpClientFactory httpClientFactory)
+        {
+            _httpClientFactory = httpClientFactory ?? throw new ArgumentNullException(nameof(httpClientFactory));
+        }
+
+        public Flurl.Http.IFlurlClient Get(Flurl.Url url)
+        {
+            return new FlurlClient(_httpClientFactory.CreateClient(url));
+        }
+
+        public void Dispose()
+        {
+            // Do Nothing
+        }
+    }
+
+    private readonly System.Net.Http.IHttpClientFactory _httpClientFactory;
     private readonly IOptions<WechatTenpayClientOptions> _wechatTenpayClientOptions;
 
-    public MyWechatClient(
+    public WechatTenpayClientFactory(
-        IHttpClientFactory httpClientFactory,
+        System.Net.Http.IHttpClientFactory httpClientFactory,
         IOptions<WechatTenpayClientOptions> wechatTenpayClientOptions)
     {
-        _httpClientFactory = httpClientFactory;
+        _httpClientFactory = httpClientFactory ?? throw new ArgumentNullException(nameof(httpClientFactory));
-        _wechatTenpayClientOptions = wechatTenpayClientOptions;
+        _wechatTenpayClientOptions = wechatTenpayClientOptions ?? throw new ArgumentNullException(nameof(wechatTenpayClientOptions));
+
+        FlurlHttp.Configure(settings => settings.FlurlClientFactory = new DelegatingFlurlClientFactory(_httpClientFactory));
     }
 
     public WechatTenpayClient CreateClient()
     {
-        var client = new WechatTenpayClient(_wechatTenpayClientOptions.Value);
+        return new WechatTenpayClient(_wechatTenpayClientOptions.Value);
-        client.Configure(settings => settings.HttpClientFactory = _httpClientFactory);
-
-        return client;
     }
 }
 ```
+
+需要强调的是，虽然 `WechatTenpayClient` 实现了 `System.IDisposable` 接口，但你不应该在 DI/IoC 中手动释放它，而是应该交给 IoC 容器自动管理它。
+
+此外你应注意，`System.Net.Http.IHttpClientFactory` 与 `Flurl.Http.Configuration.IHttpClientFactory` 是两个不同的类型，[使用时请加以区分](https://flurl.dev/docs/configuration/#httpclientfactory)。

docs/WechatTenpayV3/README.md

@@ -61,6 +61,8 @@
 
 ### 安装：
 
+提示：如果你使用 Visual Studio NuGet 管理器图形化界面，请在搜索结果中勾选“**包括预发行版**”。
+
 ```shell
 # 通过 NuGet 安装
 > Install-Package SKIT.FlurlHttpClient.Wechat.TenpayV3