コンパイラがメソッドを使用していないと判断した場合、コンパイラがメソッドを省略できる場合があること、およびコード内でメソッドを直接参照してコンパイラにメソッドを強制的に含めることでこれを回避できることを認識しています。ただし、この例では機能していないようです。
例外とコール スタックは次のとおりです。
System.ExecutionEngineException: Attempting to JIT compile method '(wrapper managed-to-native) System.Threading.Interlocked:Exchange (System.Threading.Tasks.IContinuation&,System.Threading.Tasks.IContinuation)' while running with --aot-only. See http://docs.xamarin.com/ios/about/limitations for more information.
at System.Threading.Tasks.TaskCompletionQueue`1[System.Threading.Tasks.IContinuation].TryGetNextCompletion (IContinuation& continuation) [0x00000] in <filename unknown>:0
at System.Threading.Tasks.Task.ProcessCompleteDelegates () [0x0001b] in /Developer/MonoTouch/Source/mono/mcs/class/corlib/System.Threading.Tasks/Task.cs:521
at System.Threading.Tasks.Task.HandleGenericException (System.AggregateException e) [0x0001a] in /Developer/MonoTouch/Source/mono/mcs/class/corlib/System.Threading.Tasks/Task.cs:563
at System.Threading.Tasks.Task.TrySetException (System.AggregateException aggregate) [0x0003e] in /Developer/MonoTouch/Source/mono/mcs/class/corlib/System.Threading.Tasks/Task.cs:440
at System.Threading.Tasks.TaskCompletionSource`1[System.Net.WebResponse].TrySetException (IEnumerable`1 exceptions) [0x00000] in <filename unknown>:0
at System.Threading.Tasks.TaskCompletionSource`1[System.Net.WebResponse].SetException (IEnumerable`1 exceptions) [0x00000] in <filename unknown>:0
at System.Threading.Tasks.TaskCompletionSource`1[System.Net.WebResponse].SetException (System.Exception exception) [0x00000] in <filename unknown>:0
at System.Threading.Tasks.TaskFactory`1[System.Net.WebResponse].InnerInvoke (System.Threading.Tasks.TaskCompletionSource`1 tcs, System.Func`2 endMethod, IAsyncResult l) [0x00000] in <filename unknown>:0
at System.Threading.Tasks.TaskFactory`1+<FromAsyncBeginEnd>c__AnonStorey21[System.Net.WebResponse].<>m__15 (IAsyncResult l) [0x00000] in <filename unknown>:0
at Vistian.Net.Http.HttpRequestProcessor+<BeginGetResponse>c__AnonStorey3.<>m__5 (IAsyncResult result) [0x00082] in /Users/martinstafford/Projects/Vistian/vistian/common/Vistian.Net/trunk/Vistian.Net.Portable/Http/HttpRequestProcessor.cs:441
at System.Net.WebAsyncResult.CB (System.Object unused) [0x00000] in /Developer/MonoTouch/Source/mono/mcs/class/System/System.Net/WebAsyncResult.cs:148
問題のあるクラスのコンストラクターにこの行を含めようとしましたが、それでもエラーが発生します。
object dummy = System.Threading.Interlocked.Exchange( ref dummyLock, new object());
エラーの周りのコードは次のとおりです。申し訳ありませんが、それは文脈で理解できます。「コールバック」の呼び出し時に例外がスローされます-それらのいずれか。ご覧のとおり、GetRequestStream と GetResponse の 2 つの非同期操作を含むクラスの非同期プログラミング モデルを実装しようとしています。
public static IAsyncResult BeginGetResponse(AsyncCallback callback, object state)
{
var requestProcessor = state as HttpRequestProcessor;
// create the Uri of the Host and Path in the request
// and use it to create a HttpWebRequest
Uri u = new Uri(new Uri(requestProcessor.Request.Host), requestProcessor.Request.Path);
requestProcessor.HttpWebRequest = WebRequest.Create(u) as HttpWebRequest;
// set up the header of the HttpWebRequest
requestProcessor.SetupHeader(requestProcessor.HttpWebRequest, requestProcessor.Request);
requestProcessor.WebResponse = null;
requestProcessor.RaisedException = null;
// set up an event to be used to 'timeout' the forthcoming async process
var syncRef = new System.Threading.AutoResetEvent(false);
System.Diagnostics.Debug.WriteLine(string.Format("HttpRequestProcessor.BeginGetResponse: started method={0}", requestProcessor.Request.Method));
// perform the request using the Async method
// GET and POST requests are processed differently
if (requestProcessor.Request.Method == HttpMethod.POST)
{
// create the request content using the serialiser
var bytes = requestProcessor.Encoder.Encode(requestProcessor.Request.Data, requestProcessor.Request.ContentType);
System.Diagnostics.Debug.WriteLine("HttpRequestProcessor.BeginGetResponse: BeginGetRequestStream started");
// start the async process by adding the content to the request
requestProcessor.HttpWebRequest.BeginGetRequestStream((IAsyncResult result) =>
{
// the asyncronous Get RequestStream has finished in some way
// complete the Get RequestStream process by calling EndGetRequestStream
// get the HttpWebRequest provided in the 'state' parameter and
// use it to call EndGetRequestStream
var request = result.AsyncState as HttpWebRequest;
try
{
// fill the request stream with the content
using (Stream requestStream = request.EndGetRequestStream(result))
{
requestStream.Write(bytes, 0, bytes.Length);
}
System.Diagnostics.Debug.WriteLine("HttpRequestProcessor.BeginGetResponse: EndGetRequestStream");
}
catch (Exception e)
{
// if the filling of the request stream fails, finish the Async process here
System.Diagnostics.Debug.WriteLine(string.Format("HttpRequestProcessor.BeginGetResponse: EndGetRequestSteam failed. Uri={0}", request.RequestUri));
// remember the exception, to be picked up by the subsequent call in to EndGetResponse
requestProcessor.RaisedException = e;
// clear the timeout event to indicate the async process has finished
syncRef.Set();
// call the callback as the async process is finished
callback(new AsyncResult(requestProcessor, true));
return;
}
System.Diagnostics.Debug.WriteLine("HttpRequestProcessor.BeginGetResponse: BeginGetResponse started");
// the HttpWebRequest has the request content in it
// send the request and get the response
request.BeginGetResponse((IAsyncResult responseResult) =>
{
// the Async process GetResponse has finished in some way
// get the HttpWebRequest provided as a parameter and use it
// to complete the GetRespone process
HttpWebRequest req = responseResult.AsyncState as HttpWebRequest;
try
{
requestProcessor.WebResponse = req.EndGetResponse(responseResult);
System.Diagnostics.Debug.WriteLine("HttpRequestProcessor.BeginGetResponse: EndGetResponse");
}
catch (Exception e)
{
// if getting the response fails, catch and remember the exception
// for the subsequent call in to EndGetResponse
System.Diagnostics.Debug.WriteLine(string.Format("HttpRequestProcessor.BeginGetResponse: EndGetResponse failed. Uri={0}", req.RequestUri));
requestProcessor.RaisedException = e;
}
// clear the timeout timer event
syncRef.Set();
// call the async callback
callback(new AsyncResult(requestProcessor, true));
System.Diagnostics.Debug.WriteLine("HttpRequestProcessor.BeginGetResponse: POST callback complete");
}, request);
}, requestProcessor.HttpWebRequest);
}
else
{
requestProcessor.HttpWebRequest.BeginGetResponse((IAsyncResult responseResult) =>
{
HttpWebRequest req = responseResult.AsyncState as HttpWebRequest;
try
{
requestProcessor.WebResponse = req.EndGetResponse(responseResult);
System.Diagnostics.Debug.WriteLine("HttpRequestProcessor.BeginGetResponse: EndGetResponse");
}
catch (Exception e)
{
System.Diagnostics.Debug.WriteLine(string.Format("HttpRequestProcessor.BeginGetResponse: EndGetResponse failed. Uri={0}", req.RequestUri));
requestProcessor.RaisedException = e;
}
syncRef.Set();
callback(new AsyncResult(requestProcessor, true));
System.Diagnostics.Debug.WriteLine("HttpRequestProcessor.BeginGetResponse: GET callback complete");
}, requestProcessor.HttpWebRequest);
}
// wait for the async process to finish or timeout
if (!syncRef.WaitOne(requestProcessor.Request.Timeout))
{
// async process has time out
System.Diagnostics.Debug.WriteLine("HttpRequestProcessor.BeginGetResponse: BeginGetStreamRequest timed out");
// abort the async process and create and remember an exception
// to be picked up by the call in the EndGetResponse
requestProcessor.HttpWebRequest.Abort();
requestProcessor.RaisedException = new TimeoutException("loading request stream timed out");
}
return new AsyncResult(requestProcessor, false);
}
public static WebResponse EndGetResponse(IAsyncResult result)
{
System.Diagnostics.Debug.WriteLine("HttpRequestProcessor.EndGetResponse:");
var requestProcessor = result.AsyncState as HttpRequestProcessor;
if (requestProcessor.RaisedException != null)
{
throw requestProcessor.RaisedException;
}
return requestProcessor.WebResponse;
}