ExecuteQueryAsync for Microsoft SharePoint CSOM 15/16 (On Premise)

ExecuteQueryAsync

private static async Task CSOM15ExecuteAsync(ClientRuntimeContext clientContext)
{
	try
	{
		//ScriptTypeMap.EnsureInited();
		Assembly csomRuntime = Assembly.GetAssembly(typeof(ClientRuntimeContext));
		Type scriptTypeMap = csomRuntime.GetType("Microsoft.SharePoint.Client.ScriptTypeMap");
		InvokePrivateStaticMethod(scriptTypeMap, "EnsureInited");

		//ClientRequest pendingRequest = PendingRequest;
		ClientRequest pendingRequest = clientContext.PendingRequest;

		//m_request = null;
		SetPrivateMember(typeof(ClientRuntimeContext), clientContext, "m_request", null);

		//pendingRequest.ExecuteQuery():
		{
			//m_requestStatus = ClientRequestStatus.InProgress;
			SetPrivateMember(typeof(ClientRequest), pendingRequest, "m_requestStatus", ClientRequestStatus.InProgress);

			//ChunkStringBuilder sb = BuildQuery();
			var sb = InvokePrivateMethod(typeof(ClientRequest), pendingRequest, "BuildQuery");

			//CleanupQuery();
			InvokePrivateMethod(typeof(ClientRequest), pendingRequest, "CleanupQuery");

			//ExecuteQueryToServer(sb):
			{
				//m_context.FireExecutingWebRequestEvent(new WebRequestEventArgs(pendingRequest.RequestExecutor));
				var m_context = GetPrivateMember(typeof(ClientRequest), pendingRequest, "m_context") as ClientRuntimeContext;
				InvokePrivateMethod(typeof(ClientRuntimeContext), m_context, "FireExecutingWebRequestEvent", new WebRequestEventArgs(pendingRequest.RequestExecutor));

				pendingRequest.RequestExecutor.RequestContentType = "text/xml";

				if (m_context.AuthenticationMode == ClientAuthenticationMode.Default)
				{
					pendingRequest.RequestExecutor.RequestHeaders["X-RequestForceAuthentication"] = "true";
				}

				object executeQueryMimeInfo = null;
				Type ExecuteQueryMimeInfoType = csomRuntime.GetType("Microsoft.SharePoint.Client.ClientRequest+ExecuteQueryMimeInfo");

				var SerializationContext = GetPrivateProperty(typeof(ClientRequest), pendingRequest, "SerializationContext") as SerializationContext;
				var streams = GetPrivateProperty(typeof(SerializationContext), SerializationContext, "Streams");
				if (streams != null /* && SerializationContext.Streams.Count > 0*/)
				{
					//executeQueryMimeInfo = new ExecuteQueryMimeInfo();
					var constructor = ExecuteQueryMimeInfoType.GetConstructor(BindingFlags.Public | BindingFlags.Instance, null, new Type[0], null);
					executeQueryMimeInfo = constructor.Invoke(null);

					var contentType = (string)ExecuteQueryMimeInfoType.GetProperty("ContentType").GetValue(executeQueryMimeInfo);
					pendingRequest.RequestExecutor.RequestContentType = contentType;
				}

				var requestStream = pendingRequest.RequestExecutor.GetRequestStream();
				if (executeQueryMimeInfo != null)
				{
					//WriteMimeStream(executeQueryMimeInfo, sb, requestStream);
					InvokePrivateMethod(typeof(ClientRequest), pendingRequest, "WriteMimeStream", executeQueryMimeInfo, sb, requestStream);
				}
				else
				{
					Type ChunkStringBuilderType = csomRuntime.GetType("Microsoft.SharePoint.Client.ChunkStringBuilder");

					//sb.WriteContentAsUTF8(requestStream);
					InvokePublicMethod(ChunkStringBuilderType, sb, "WriteContentAsUTF8", requestStream);
				}

				await requestStream.FlushAsync();
				requestStream.Close();

				var spWebRequestExecutorType = csomRuntime.GetType("Microsoft.SharePoint.Client.SPWebRequestExecutor");

				if (pendingRequest.RequestExecutor.GetType() == spWebRequestExecutorType)
				{
					//m_webRequest.GetRequestStream().Close();
					var m_webRequest = GetPrivateMember(spWebRequestExecutorType, pendingRequest.RequestExecutor, "m_webRequest") as System.Net.HttpWebRequest;
					var stream = await m_webRequest.GetRequestStreamAsync();
					stream.Close();

					//m_webResponse = (HttpWebResponse)m_webRequest.GetResponse();
					var m_webResponse = await m_webRequest.GetResponseAsync();
					SetPrivateMember(spWebRequestExecutorType, pendingRequest.RequestExecutor, "m_webResponse", m_webResponse);
				}
				else
				{
					pendingRequest.RequestExecutor.Execute();
				}
				InvokePrivateMethod(typeof(ClientRequest), pendingRequest, "ProcessResponse");
			}
		}
	}
	catch(Exception e)
	{
		if(e.InnerException != null)
		{
			throw e.InnerException;
		}
		else
		{
			throw e;
		}
	}
}


private static object InvokePrivateMethod(Type type, object obj, string methodName, params object[] arguments)
{
	MethodInfo dynMethod = type.GetMethod(methodName, BindingFlags.NonPublic | BindingFlags.Instance);
	return dynMethod.Invoke(obj, arguments);
}

private static object InvokePublicMethod(Type type, object obj, string methodName, params object[] arguments)
{
	MethodInfo dynMethod = type.GetMethod(methodName, BindingFlags.Public | BindingFlags.Instance);
	return dynMethod.Invoke(obj, arguments);
}

private static object InvokePrivateStaticMethod(Type type, string methodName, params object[] arguments)
{
	MethodInfo dynMethod = type.GetMethod(methodName, BindingFlags.NonPublic | BindingFlags.Static);
	return dynMethod.Invoke(type, arguments);
}

private static object GetPrivateMember(Type type, object obj, string memberName)
{
	var fieldInfo = type.GetField(memberName, BindingFlags.Instance | BindingFlags.NonPublic);
	return fieldInfo.GetValue(obj);
}

private static object GetPrivateProperty(Type type, object obj, string memberName)
{
	var fieldInfo = type.GetProperty(memberName, BindingFlags.Instance | BindingFlags.NonPublic);
	return fieldInfo.GetValue(obj);
}

private static void SetPrivateMember(Type type, object obj, string memberName, object value)
{
	var fieldInfo = type.GetField(memberName, BindingFlags.Instance | BindingFlags.NonPublic);
	fieldInfo.SetValue(obj, value);
}

private static object GetStaticPropertyValue(Type type, string propertyName)
{
	var prop = type.GetProperty("Test", BindingFlags.Static | BindingFlags.NonPublic);
	return prop.GetValue(type);
}