使用代理后面的.Net Core 2.0连接到SOAP服务

我正在使用Visual Studio 2017。

I'm using Visual Studio 2017.

我注意到，当位于.NET Core 2.0后面时，无法从.Net Core 2.0连接到SOAP服务。代理（当直接连接到Internet时它正在工作，并且当从.Net Core 1.1应用程序通过代理连接时它也正在工作）。

I have noticed that it was not possible to connect to a SOAP service from a .Net Core 2.0 when being behind a proxy (when connected directly to the internet it's working and when connecting through the proxy from a .Net Core 1.1 app it's working too).

我创建了一个小测试程序（控制台应用程序）调用公共SOAP服务（ http://www.webservicex.net/globalweather.asmx ）。
通过更改该程序的目标（.Net Core 1.1 / .Net Core 2.0），我可以重现此问题。

I have created a little test program (Console app) that calls a public SOAP service (http://www.webservicex.net/globalweather.asmx). By changing the target of this program (.Net Core 1.1 / .Net Core 2.0) I can reproduce the problem.

以下是示例代码（ VS 2017的Connected Services组件已生成用于连接到Web服务的类）。

Here is the sample code (the classes for connecting to the web service have been generated with VS 2017's Connected Services component):

BasicHttpBinding binding = new BasicHttpBinding();

EndpointAddress address = new EndpointAddress("http://www.webservicex.net/globalweather.asmx");

GlobalWeatherSoapClient client = new GlobalWeatherSoapClient(binding, address);

var response = client.GetCitiesByCountryAsync("France").Result;

我已经完成了网络捕获（使用Wireshark），当发生此问题时，我看不到任何HTTP请求从我的计算机出来。
有人知道出了什么问题吗？

I have done a network capture (with Wireshark) and when this problem happens I can see no HTTP request coming out from my computer. Does anybody know what is going wrong ? Maybe I am not calling this service the right way.

预先感谢