Question

我正在使用他们的hosted page integration与替代付款进行整合。他们的C＃SDK暂时没有这种集成，但正如你所看到的那样非常简单，我发了一个小类来发送post请求并获得JSON响应。

我测试了我在PostMan和cURL上发送的json对象，两者都工作，也是认证头，所以我认为它们不是问题所在。这是我班级的构造函数：

public AlternativePaymentsCli(string apiSecretKey)
{
    this._apiSecretKey = apiSecretKey;

    _httpClient = new HttpClient();
    _httpClient.DefaultRequestHeaders.Accept
        .Add(new MediaTypeWithQualityHeaderValue("application/json"));

    var authInfo = _apiSecretKey;
    authInfo = Convert.ToBase64String(System.Text.ASCIIEncoding.ASCII.GetBytes(string.Format("{0}:", _apiSecretKey)));

    // The two line below because I saw in an answer on stackoverflow.
    _httpClient.DefaultRequestHeaders.Add("Connection", "Keep-Alive"); 
    _httpClient.DefaultRequestHeaders.Add("Keep-Alive", "3600");

    _httpClient.DefaultRequestHeaders.UserAgent.ParseAdd("Anything.com custom client v1.0");
    _httpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Basic", authInfo);

}

我发布数据的方法：

public string CreateHostedPageTransaction(HostedPageRequest req) 
{
    var settings = new JsonSerializerSettings { NullValueHandling = NullValueHandling.Ignore };

    // I send this same json content on PostMan and it works. The json is not the problem
    var content = new StringContent(JsonConvert.SerializeObject(req, settings), Encoding.UTF8, "application/json");
    var response = _httpClient.PostAsync(this._baseUrl + "/transactions/hosted", content).Result;
    var responseText = response.Content.ReadAsStringAsync().GetAwaiter().GetResult();

    if (response.IsSuccessStatusCode)
        return responseText;

    return "";
}

然后我在PostAsync行中收到此错误：An existing connection was forcibly closed by the remote host。这是错误细节：

[SocketException (0x2746): An existing connection was forcibly closed by the remote host]
   System.Net.Sockets.Socket.EndReceive(IAsyncResult asyncResult) +8192811
   System.Net.Sockets.NetworkStream.EndRead(IAsyncResult asyncResult) +47

[IOException: Unable to read data from the transport connection: An existing connection was forcibly closed by the remote host.]
   System.Net.TlsStream.EndWrite(IAsyncResult asyncResult) +294
   System.Net.ConnectStream.WriteHeadersCallback(IAsyncResult ar) +149

[WebException: The underlying connection was closed: An unexpected error occurred on a send.]
   System.Net.HttpWebRequest.EndGetRequestStream(IAsyncResult asyncResult, TransportContext& context) +324
   System.Net.Http.HttpClientHandler.GetRequestStreamCallback(IAsyncResult ar) +137

[HttpRequestException: An error occurred while sending the request.]

我正在使用C＃4.5，Asp.Net MVC。我一直在阅读相同错误的答案，到目前为止，他们都没有解决我的问题。我在这段代码中缺少什么？

感谢您的帮助

Answer 1

我没有在您的代码示例中看到您在哪里设置_baseUrl的值，但我假设这是在某处完成的。我还假设由于这与付款有关，因此网址为HTTPS。如果远程主机已禁用TLS 1.0并且您的连接以TLS 1.0的形式进入，则可能会导致该行为。我知道C＃4.6默认启用了TLS 1.0 / 1.1 / 1.2支持，但我认为C＃4.6仍然默认只支持SSL3 / TLS 1.0，即使支持TLS 1.1和1.2。如果这是问题的原因，您可以使用以下代码手动将TLS 1.1和1.2添加到启用的值。

System.Net.ServicePointManager.SecurityProtocol |= SecurityProtocolType.Tls11 | SecurityProtocolType.Tls12;

Answer 2

如果您使用的是.Net 4.0，则未定义SecurityProtocolType.Tls11和SecurityProtocolType.Tls2，因此您可以使用下面的硬编码值。

ServicePointManager.SecurityProtocol = (SecurityProtocolType)3072;

Answer 3

如this excellent answer中所述，对于类似问题，无需更改代码即可解决该问题：

将Web项目重新定位为 .Net 4.6 + ，然后按以下方式更新web.config：

<system.web>
  <compilation targetFramework="4.6" /> 
  <httpRuntime targetFramework="4.6" /> 
</system.web>

Answer 4

这对我有用，第一行确保协议$Src = "C:\Folder3\" $Dst = "C:\Save\" Get-ChildItem -Path $Src -Recurse -Name "File2.txt" | Where-Object {$_.PSIsContainer} | ForEach-Object {[System.IO.Path]::GetDirectoryName($_); New-Item -Path $Dst -Name $_}和ssl3，第二行忽略任何潜在的证书错误（忽略并继续，如过期的证书。）：

TLS1.2

Answer 5

对我来说，此错误是由于忘记配置代理服务器引起的。使用以下代码构造HttpClient为我的.NET 4.7.2应用程序解决了该问题：

var httpClientHandler = new HttpClientHandler { Proxy = WebRequest.GetSystemWebProxy() };
var httpClient = new HttpClient(httpClientHandler);

希望这对某人有帮助。

C＃HttpClient远程主机强制关闭现有连接

5 个答案: