为什么Xamarin iOS中的WebRequest在ipv6环境中失败？

Question

我设置以下https://developer.apple.com/library/content/documentation/NetworkingInternetWeb/Conceptual/NetworkingOverview/UnderstandingandPreparingfortheIPv6Transition/UnderstandingandPreparingfortheIPv6Transition.html#//apple_ref/doc/uid/TP40010220-CH213-SW1

我有一个非常简单的iOS Xamarin项目，我做什么，但本地IPv6环境：

WebRequest req = WebRequest.Create("http://109.68.230.138"); 
WebResponse response = req.GetResponse(); //exception 
var dataStream = response.GetResponseStream(); 
StreamReader reader = new StreamReader(dataStream); 
string responseFromServer = reader.ReadToEnd(); 

在第2行，我得到下面的异常。如果有人知道这应该如何表现或如何让这个运行，那将是非常棒的。我猜想传递ipv4地址仍然是一个常见的用例。

Unhandled Exception: 
System.Net.WebException: Error: ConnectFailure (Network is unreachable) ---> System.Net.Sockets.SocketException: Network is unreachable 
    at System.Net.Sockets.Socket.Connect (System.Net.EndPoint remoteEP) [0x000cb] in /Users/builder/data/lanes/3859/b638977c/source/xamarin-macios/_ios-build/Library/Frameworks/Xamarin.iOS.framework/Versions/git/src/mono/mcs/class/System/System.Net.Sockets/Socket.cs:1313 
    at System.Net.WebConnection.Connect (System.Net.HttpWebRequest request) [0x001c2] in /Users/builder/data/lanes/3859/b638977c/source/xamarin-macios/_ios-build/Library/Frameworks/Xamarin.iOS.framework/Versions/git/src/mono/mcs/class/System/System.Net/WebConnection.cs:195 
    --- End of inner exception stack trace --- 
    at System.Net.HttpWebRequest.EndGetResponse (System.IAsyncResult asyncResult) [0x00065] in /Users/builder/data/lanes/3859/b638977c/source/xamarin-macios/_ios-build/Library/Frameworks/Xamarin.iOS.framework/Versions/git/src/mono/mcs/class/System/System.Net/HttpWebRequest.cs:1025 
    at System.Net.HttpWebRequest.GetResponse() [0x0000e] in /Users/builder/data/lanes/3859/b638977c/source/xamarin-macios/_ios-build/Library/Frameworks/Xamarin.iOS.framework/Versions/git/src/mono/mcs/class/System/System.Net/HttpWebRequest.cs:1037 
    at Test.iOS.AppDelegate.FinishedLaunching (UIKit.UIApplication application, Foundation.NSDictionary launchOptions) [0x0000d] in /Users/xxx/Projects/Test/iOS/AppDelegate.cs:26 
    at (wrapper managed-to-native) UIKit.UIApplication:UIApplicationMain (int,string[],intptr,intptr) 
    at UIKit.UIApplication.Main (System.String[] args, System.IntPtr principal, System.IntPtr delegate) [0x00005] in /Users/builder/data/lanes/3859/b638977c/source/xamarin-macios/src/UIKit/UIApplication.cs:79 
    at UIKit.UIApplication.Main (System.String[] args, System.String principalClassName, System.String delegateClassName) [0x00038] in /Users/builder/data/lanes/3859/b638977c/source/xamarin-macios/src/UIKit/UIApplication.cs:63 
    at Test.iOS.Application.Main (System.String[] args) [0x00008] in /Users/xxx/Projects/Test/iOS/Main.cs:17 
2016-11-09 09:34:32.194 Test.iOS[763:313310] Unhandled managed exception: 
Error: ConnectFailure (Network is unreachable) (System.Net.WebException) 
    at System.Net.HttpWebRequest.EndGetResponse (System.IAsyncResult asyncResult) [0x00065] in /Users/builder/data/lanes/3859/b638977c/source/xamarin-macios/_ios-build/Library/Frameworks/Xamarin.iOS.framework/Versions/git/src/mono/mcs/class/System/System.Net/HttpWebRequest.cs:1025 
    at System.Net.HttpWebRequest.GetResponse() [0x0000e] in /Users/builder/data/lanes/3859/b638977c/source/xamarin-macios/_ios-build/Library/Frameworks/Xamarin.iOS.framework/Versions/git/src/mono/mcs/class/System/System.Net/HttpWebRequest.cs:1037 
    at Test.iOS.AppDelegate.FinishedLaunching (UIKit.UIApplication application, Foundation.NSDictionary launchOptions) [0x0000d] in /Users/xxx/Projects/Test/iOS/AppDelegate.cs:26 
    at (wrapper managed-to-native) UIKit.UIApplication:UIApplicationMain (int,string[],intptr,intptr) 
    at UIKit.UIApplication.Main (System.String[] args, System.IntPtr principal, System.IntPtr delegate) [0x00005] in /Users/builder/data/lanes/3859/b638977c/source/xamarin-macios/src/UIKit/UIApplication.cs:79 
    at UIKit.UIApplication.Main (System.String[] args, System.String principalClassName, System.String delegateClassName) [0x00038] in /Users/builder/data/lanes/3859/b638977c/source/xamarin-macios/src/UIKit/UIApplication.cs:63 
    at Test.iOS.Application.Main (System.String[] args) [0x00008] in /Users/xxx/Projects/Test/iOS/Main.cs:17 
--- inner exception --- 
Network is unreachable (System.Net.Sockets.SocketException) 
    at System.Net.Sockets.Socket.Connect (System.Net.EndPoint remoteEP) [0x000cb] in /Users/builder/data/lanes/3859/b638977c/source/xamarin-macios/_ios-build/Library/Frameworks/Xamarin.iOS.framework/Versions/git/src/mono/mcs/class/System/System.Net.Sockets/Socket.cs:1313 
    at System.Net.WebConnection.Connect (System.Net.HttpWebRequest request) [0x001c2] in /Users/builder/data/lanes/3859/b638977c/source/xamarin-macios/_ios-build/Library/Frameworks/Xamarin.iOS.framework/Versions/git/src/mono/mcs/class/System/System.Net/WebConnection.cs:195 
2016-11-09 09:34:32.195 Test.iOS[763:313310] critical: Stacktrace: 

2016-11-09 09:34:32.195 Test.iOS[763:313310] critical: 
Native stacktrace: 

2016-11-09 09:34:32.265 Test.iOS[763:313310] critical: 0 libmonosgen-2.0.dylib    0x00000001001abd0c mono_handle_native_sigsegv + 260 
2016-11-09 09:34:32.266 Test.iOS[763:313310] critical: 1 libsystem_platform.dylib   0x0000000192eec348 _sigtramp + 52 
2016-11-09 09:34:32.266 Test.iOS[763:313310] critical: 2 libsystem_pthread.dylib    0x0000000192ef2450 pthread_kill + 112 
2016-11-09 09:34:32.266 Test.iOS[763:313310] critical: 3 libsystem_c.dylib     0x0000000192d9e3e0 abort + 140 
2016-11-09 09:34:32.267 Test.iOS[763:313310] critical: 4 libxamarin-debug.dylib    0x0000000100480d90 _ZL20print_all_exceptionsP10MonoObject + 0 
2016-11-09 09:34:32.267 Test.iOS[763:313310] critical: 5 libmonosgen-2.0.dylib    0x00000001001ac59c mono_invoke_unhandled_exception_hook + 100 
2016-11-09 09:34:32.267 Test.iOS[763:313310] critical: 6 libmonosgen-2.0.dylib    0x00000001001ab830 mono_handle_exception_internal + 3860 
2016-11-09 09:34:32.268 Test.iOS[763:313310] critical: 7 libmonosgen-2.0.dylib    0x00000001001aa910 mono_handle_exception + 40 
2016-11-09 09:34:32.268 Test.iOS[763:313310] critical: 8 libmonosgen-2.0.dylib    0x00000001001a1be4 mono_arm_throw_exception + 216 
2016-11-09 09:34:32.268 Test.iOS[763:313310] critical: 9 libmscorlib.dll.dylib    0x00000001007a9918 throw_exception + 168 
2016-11-09 09:34:32.268 Test.iOS[763:313310] critical: 10 libSystem.dll.dylib     0x0000000100bbac44 System_Net_HttpWebRequest_EndGetResponse_System_IAsyncResult + 388 
2016-11-09 09:34:32.269 Test.iOS[763:313310] critical: 11 libSystem.dll.dylib     0x0000000100bbacc0 System_Net_HttpWebRequest_GetResponse + 112 
2016-11-09 09:34:32.269 Test.iOS[763:313310] critical: 12 libTest.iOS.exe.dylib    0x00000001000770b4 Test_iOS_AppDelegate_FinishedLaunching_UIKit_UIApplication_Foundation_NSDictionary + 276 
2016-11-09 09:34:32.269 Test.iOS[763:313310] critical: 13 libmscorlib.dll.dylib    0x0000000100786db4 wrapper_runtime_invoke_object_runtime_invoke_dynamic_intptr_intptr_intptr_intptr + 244 
2016-11-09 09:34:32.269 Test.iOS[763:313310] critical: 14 libmonosgen-2.0.dylib    0x00000001001ba1dc mono_jit_runtime_invoke + 1772 
2016-11-09 09:34:32.270 Test.iOS[763:313310] critical: 15 libmonosgen-2.0.dylib    0x000000010022ad0c do_runtime_invoke + 112 
2016-11-09 09:34:32.270 Test.iOS[763:313310] critical: 16 libmonosgen-2.0.dylib    0x000000010022ac68 mono_runtime_invoke + 208 
2016-11-09 09:34:32.270 Test.iOS[763:313310] critical: 17 Test.iOS       0x000000010005c62c _ZL30native_to_managed_trampoline_5P11objc_objectP13objc_selectorPP11_MonoMethodP13UIApplicationP12NSDictionaryPKcSB_SB_SB_ + 692 
2016-11-09 09:34:32.270 Test.iOS[763:313310] critical: 18 Test.iOS       0x000000010005c368 -[AppDelegate application:didFinishLaunchingWithOptions:] + 96 
2016-11-09 09:34:32.271 Test.iOS[763:313310] critical: 19 UIKit        0x0000000199d20100 <redacted> + 400 
2016-11-09 09:34:32.271 Test.iOS[763:313310] critical: 20 UIKit        0x0000000199f30858 <redacted> + 3524 
2016-11-09 09:34:32.271 Test.iOS[763:313310] critical: 21 UIKit        0x0000000199f365c8 <redacted> + 1656 
2016-11-09 09:34:32.271 Test.iOS[763:313310] critical: 22 UIKit        0x0000000199f4ae60 <redacted> + 48 
2016-11-09 09:34:32.272 Test.iOS[763:313310] critical: 23 UIKit        0x0000000199f335ac <redacted> + 168 
2016-11-09 09:34:32.272 Test.iOS[763:313310] critical: 24 FrontBoardServices     0x0000000195a018bc <redacted> + 36 
2016-11-09 09:34:32.272 Test.iOS[763:313310] critical: 25 FrontBoardServices     0x0000000195a01728 <redacted> + 176 
2016-11-09 09:34:32.272 Test.iOS[763:313310] critical: 26 FrontBoardServices     0x0000000195a01ad0 <redacted> + 56 
2016-11-09 09:34:32.273 Test.iOS[763:313310] critical: 27 CoreFoundation      0x0000000193e08278 <redacted> + 24 
2016-11-09 09:34:32.273 Test.iOS[763:313310] critical: 28 CoreFoundation      0x0000000193e07bc0 <redacted> + 524 
2016-11-09 09:34:32.273 Test.iOS[763:313310] critical: 29 CoreFoundation      0x0000000193e057c0 <redacted> + 804 
2016-11-09 09:34:32.273 Test.iOS[763:313310] critical: 30 CoreFoundation      0x0000000193d34048 CFRunLoopRunSpecific + 444 
2016-11-09 09:34:32.274 Test.iOS[763:313310] critical: 31 UIKit        0x0000000199d192b0 <redacted> + 608 
2016-11-09 09:34:32.274 Test.iOS[763:313310] critical: 32 UIKit        0x0000000199d14034 UIApplicationMain + 208 
2016-11-09 09:34:32.274 Test.iOS[763:313310] critical: 33 libXamarin.iOS.dll.dylib   0x0000000100514fb4 wrapper_managed_to_native_UIKit_UIApplication_UIApplicationMain_int_string___intptr_intptr + 324 
2016-11-09 09:34:32.274 Test.iOS[763:313310] critical: 34 libXamarin.iOS.dll.dylib   0x00000001004d61ac UIKit_UIApplication_Main_string___intptr_intptr + 44 
2016-11-09 09:34:32.275 Test.iOS[763:313310] critical: 35 libXamarin.iOS.dll.dylib   0x00000001004d616c UIKit_UIApplication_Main_string___string_string + 172 
2016-11-09 09:34:32.275 Test.iOS[763:313310] critical: 36 libTest.iOS.exe.dylib    0x0000000100076de0 Test_iOS_Application_Main_string__ + 160 
2016-11-09 09:34:32.275 Test.iOS[763:313310] critical: 37 libmscorlib.dll.dylib    0x0000000100786db4 wrapper_runtime_invoke_object_runtime_invoke_dynamic_intptr_intptr_intptr_intptr + 244 
2016-11-09 09:34:32.275 Test.iOS[763:313310] critical: 38 libmonosgen-2.0.dylib    0x00000001001ba1dc mono_jit_runtime_invoke + 1772 
2016-11-09 09:34:32.276 Test.iOS[763:313310] critical: 39 libmonosgen-2.0.dylib    0x000000010022ad0c do_runtime_invoke + 112 
2016-11-09 09:34:32.276 Test.iOS[763:313310] critical: 40 libmonosgen-2.0.dylib    0x000000010022d2f0 mono_runtime_exec_main + 832 
2016-11-09 09:34:32.276 Test.iOS[763:313310] critical: 41 libmonosgen-2.0.dylib    0x000000010022cf0c mono_runtime_run_main + 764 
2016-11-09 09:34:32.276 Test.iOS[763:313310] critical: 42 libmonosgen-2.0.dylib    0x000000010019e7f8 mono_jit_exec + 236 
2016-11-09 09:34:32.277 Test.iOS[763:313310] critical: 43 libxamarin-debug.dylib    0x000000010048dcd8 xamarin_main + 2168 
2016-11-09 09:34:32.277 Test.iOS[763:313310] critical: 44 Test.iOS       0x000000010005de50 main + 96 
2016-11-09 09:34:32.277 Test.iOS[763:313310] critical: 45 libdyld.dylib      0x0000000192d185b8 <redacted> + 4 
2016-11-09 09:34:32.277 Test.iOS[763:313310] critical: 
================================================================= 
Got a SIGABRT while executing native code. This usually indicates 
a fatal error in the mono runtime or one of the native libraries 
used by your application. 
================================================================= 

Answer 1

您不能使用IPv4地址文字。这是一种自动失败和应用程序拒绝，因为它们不适用于纯IPv6环境。您必须改用主机名。

Answer 2

苹果似乎在纯ipv6环境中测试，所以任何直接调用都会失败。这是他们的意见时，他们昨天没我的应用程序：

请运行在设备上的应用程序，同时连接到IPv6网络 （所有的应用程序必须支持IPv6），以确定问题的（一个或多个），然后修改和 重新提交您的应用以供审核。

如果我们误解了您应用的预期行为，请回复 此消息在Resolution Center中，以提供有关这些 功能如何工作的信息。

对于新的应用程序，从 设备上卸载您应用程序的所有先前版本，然后安装并按照步骤重现问题。 如需更新，请安装新版本作为先前的 版本的更新，然后按照步骤重现问题。

资源

有关支持IPv6网络的信息，请参阅 Supporting IPv6 DNS64/NAT64 Networks and About Networking。