我正在使用ModernHttpClient库，我正在尝试从httpclient的响应中获取cookie
public static async Task<String> loginUser()
{
var values = new List<KeyValuePair<string, string>>
{
new KeyValuePair<string, string>("username", "*****"),
new KeyValuePair<string, string>("password", "*****"),
};
NativeCookieHandler cookieHandler = new NativeCookieHandler();
NativeMessageHandler messageHandler = new NativeMessageHandler(false, false, cookieHandler);
var httpClient = new HttpClient(messageHandler);
var response = await httpClient.PostAsync(RestApiPaths.LOGIN, new FormUrlEncodedContent(values));
response.EnsureSuccessStatusCode();
String resultString = await response.Content.ReadAsStringAsync();
System.Diagnostics.Debug.WriteLine("resultString: " + resultString);
IEnumerable<Cookie> responseCookies = cookieHandler.Cookies;
Cookie mCookie = responseCookies.FirstOrDefault();
RestApiPaths.mCookie = mCookie;
return resultString;
}
，但下线给出了错误：
IEnumerable<Cookie> responseCookies = cookieHandler.Cookies;
错误：
MonoDroid] UNHANDLED EXCEPTION:
[MonoDroid] System.Exception: You're referencing the Portable version in your App - you need to reference the platform (iOS/Android) version
[MonoDroid] at Gogch.MyClass+<loginUser>c__async0.MoveNext () <0x9e0d9e08 + 0x004b8> in <filename unknown>:0
[MonoDroid] --- End of stack trace from previous location where exception was thrown ---
[MonoDroid] at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () <0x9d3a3670 + 0x00024> in <filename unknown>:0
[MonoDroid] at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Threading.Tasks.Task task) <0x9d3a2ff8 + 0x000bb> in <filename unknown>:0
[MonoDroid] at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Threading.Tasks.Task task) <0x9d3a2dd0 + 0x0008b> in <filename unknown>:0
[MonoDroid] at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd (System.Threading.Tasks.Task task) <0x9d6ecaa8 + 0x0003f> in <filename unknown>:0
[MonoDroid] at System.Runtime.CompilerServices.TaskAwaiter`1[TResult].GetResult () <0xa1f0fa18 + 0x0001b> in <filename unknown>:0
[MonoDroid] at Gogch.Droid.MainActivity+<button_OnClick>c__async0.MoveNext () <0xaf58c608 + 0x00137> in <filename unknown>:0
[MonoDroid] --- End of stack trace from previous location where exception was thrown ---
[MonoDroid] at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () <0x9d3a3670 + 0x00024> in <filename unknown>:0
[MonoDroid] at System.Runtime.CompilerServices.AsyncMethodBuilderCore.<ThrowAsync>m__0 (System.Object state) <0x9d3a4488 + 0x0003f> in <filename unknown>:0
[MonoDroid] at Android.App.SyncContext+<Post>c__AnonStorey0.<>m__0 () <0xa1f0f968 + 0x00027> in <filename unknown>:0
[MonoDroid] at Java.Lang.Thread+RunnableImplementor.Run () <0xa1f0f7b8 + 0x0003f> in <filename unknown>:0
[MonoDroid] at Java.Lang.IRunnableInvoker.n_Run (IntPtr jnienv, IntPtr native__this) <0xa1f0f710 + 0x0003f> in <filename unknown>:0
[MonoDroid] at (wrapper dynamic-method) System.Object:ba036dc5-deef-4850-b986-e1e85c84e6de (intptr,intptr)
[art] JNI RegisterNativeMethods: attempt to register 0 native methods for android.runtime.JavaProxyThrowable
[AndroidRuntime] Shutting down VM
[AndroidRuntime] FATAL EXCEPTION: main
[AndroidRuntime] Process: com.cinch.gogch, PID: 18910
[AndroidRuntime] java.lang.RuntimeException: java.lang.reflect.InvocationTargetException
[AndroidRuntime] at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
[AndroidRuntime] Caused by: java.lang.reflect.InvocationTargetException
[AndroidRuntime] at java.lang.reflect.Method.invoke(Native Method)
[AndroidRuntime] at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:728)
[AndroidRuntime] ... 1 more
[AndroidRuntime] Caused by: android.runtime.JavaProxyThrowable: System.Exception: You're referencing the Portable version in your App - you need to reference the platform (iOS/Android) version
[AndroidRuntime] at Gogch.MyClass+<loginUser>c__async0.MoveNext () <0x9e0d9e08 + 0x004b8> in <filename unknown>:0
[AndroidRuntime] --- End of stack trace from previous location where exception was thrown ---
[AndroidRuntime] at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () <0x9d3a3670 + 0x00024> in <filename unknown>:0
[AndroidRuntime] at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Threading.Tasks.Task task) <0x9d3a2ff8 + 0x000bb> in <filename unknown>:0
[AndroidRuntime] at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Threading.Tasks.Task task) <0x9d3a2dd0 + 0x0008b> in <filename unknown>:0
[AndroidRuntime] at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd (System.Threading.Tasks.Task task) <0x9d6ecaa8 + 0x0003f> in <filename unknown>:0
[AndroidRuntime] at System.Runtime.CompilerServices.TaskAwaiter`1[TResult].GetResult () <0xa1f0fa18 + 0x0001b> in <filename unknown>:0
[AndroidRuntime] at Gogch.Droid.MainActivity+<button_OnClick>c__async0.MoveNext () <0xaf58c608 + 0x00137> in <filename unknown>:0
[AndroidRuntime] --- End of stack trace from previous location where exception was thrown ---
[AndroidRuntime] at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () <0x9d3a3670 + 0x00024> in <filename unknown>:0
[AndroidRuntime] at System.Runtime.CompilerServices.AsyncMethodBuilderCore.<ThrowAsync>m__0 (System.Object state) <0x9d3a4488 + 0x0003f> in <filename unknown>:0
[AndroidRuntime] at Android.App.SyncContext+<Post>c__AnonStorey0.<>m__0 () <0xa1f0f968 + 0x00027> in <filename unknown>:0
[AndroidRuntime] at Java.Lang.Thread+RunnableImplementor.Run () <0xa1f0f7b8 + 0x0003f> in <filename unknown>:0
[AndroidRuntime] at Java.Lang.IRunnableInvoker.n_Run (IntPtr jnienv, IntPtr native__this) <0xa1f0f710 + 0x0003f> in <filename unknown>:0
[AndroidRuntime] at (wrapper dynamic-method) System.Object:ba036dc5-deef-4850-b986-e1e85c84e6de (intptr,intptr)
[AndroidRuntime] at mono.java.lang.RunnableImplementor.n_run(Native Method)
[AndroidRuntime] at mono.java.lang.RunnableImplementor.run(RunnableImplementor.java:30)
[AndroidRuntime] at android.os.Handler.handleCallback(Handler.java:746)
[AndroidRuntime] at android.os.Handler.dispatchMessage(Handler.java:95)
[AndroidRuntime] at android.os.Looper.loop(Looper.java:148)
[AndroidRuntime] at android.app.ActivityThread.main(ActivityThread.java:5443)
[AndroidRuntime] ... 3 more
我在PCL中有此代码。为什么我会遇到这个错误？我如何正确获取cookie？
编辑：
现在，我的PCL和iOS项目中都有ModernHttpClient库，以使其正常工作。如果我从iOS项目中删除它。我遇到相同的错误。
对于将来的Googleers：当您将某些Nuget参考（例如modernhttpclient-updated）更新为目标Xamarin.Android 8.1（例如）时，您的应用程序目标是Xamarin.Android 6.0：在这种情况下，它可能会发生。。
请注意Nuget警告！
当您添加解决方案的引用时，您是否添加了对PCL项目的参考以及iOS和Android项目？
它是相同的Nuget软件包，但是Android软件包添加了
的引用〜 packages ModernHttpClient.2.4.2 lib monoandroid
ios获得
的引用〜 packages ModernHttpClient.2.4.2 lib Xamarin.ios10
我假设这是在Visual Studio中？也许只是卸载包装并重新安装它（并在解决方案级别安装）。
确保您的项目对汇编有正确的参考：
- Android：在
MonoAndroid文件夹中 - ios：在
Xamarin.iOS10文件夹（或MonoTouch文件夹）中 - pcl：在
Portable-Net45+WinRT45+WP8+WPA81文件夹中
如果这无济
- Xamarin.ios提供了 ModernHttpClient 的功能（虽然有限）。
- 实际上，
ModernHttpClient.NativeMessageHandler对cookieHandler参数无能为力。您可以在源代码（Android，iOS）中检查它。而且，您可以在本地处理Cookie，而不是使用 ModernHttpClient 实现，请参阅源代码以获取示例（Android，ios）。
尤金（Eugene）和海森伯格（Heisenberg）解释，更多的澄清。您被"诱饵和开关"所困，