IAsyncResult インターフェイス
アセンブリ: mscorlib (mscorlib.dll 内)
構文
解説
IAsyncResult インターフェイスは、非同期操作できるメソッドが格納されたクラスで実装します。これは FileStream.BeginRead などの非同期操作を開始するメソッドの戻り値の型を示すと同時に、FileStream.EndRead などの非同期操作を終了させるメソッドの 3 番目のパラメータの型を示します。IAsyncResult オブジェクトも、非同期操作が完了したときに、AsyncCallback デリゲートによって呼び出されるメソッドに渡されます。
IAsyncResult インターフェイスをサポートするオブジェクトは、非同期操作のステータス情報を格納するほか、同期操作が完了したときにその旨をスレッドに通知できるようにする同期オブジェクトを提供します。
IAsyncResult インターフェイスの使用方法の詳細については、「同期メソッドの非同期呼び出し」を参照してください。
IAsyncResult を使用して非同期操作の戻り値を取得する方法を次のサンプルで示します。
' Asynchronous Callback method. Public Shared Sub MyCallback(ar As IAsyncResult) ' Obtains the last parameter of the delegate call. Dim value As Integer = Convert.ToInt32(ar.AsyncState) ' Obtains return value from the delegate call using EndInvoke. Dim aResult As AsyncResult = CType(ar, AsyncResult) Dim temp As SampSyncSqrDelegate = CType(aResult.AsyncDelegate, SampSyncSqrDelegate) Dim result As Integer = temp.EndInvoke(ar) Console.Write("Simple.SomeMethod (AsyncCallback): Result of ") Console.WriteLine("{0} in SampleSynchronized.Square is {1} ", value, result) End Sub 'MyCallback
// Asynchronous Callback method. public static void MyCallback(IAsyncResult ar) { // Obtains the last parameter of the delegate call. int value = Convert.ToInt32(ar.AsyncState); // Obtains return value from the delegate call using EndInvoke. AsyncResult aResult = (AsyncResult)ar; SampSyncSqrDelegate temp = (SampSyncSqrDelegate)aResult.AsyncDelegate; int result = temp.EndInvoke(ar); Console.Write("Simple.SomeMethod (AsyncCallback): Result of "); Console.WriteLine("{0} in SampleSynchronized.Square is {1} ", value, result); }
// Asynchronous Callback method. static void MyCallback( IAsyncResult^ ar ) { // Obtains the last parameter of the delegate call. int value = Convert::ToInt32( ar->AsyncState ); // Obtains return value from the delegate call using EndInvoke. AsyncResult^ aResult = dynamic_cast<AsyncResult^>(ar); SampSyncSqrDelegate^ temp = static_cast<SampSyncSqrDelegate^>(aResult->AsyncDelegate); int result = temp->EndInvoke( ar ); Console::Write( "Simple::SomeMethod (AsyncCallback): Result of " ); Console::WriteLine( " {0} in SampleSynchronized::Square is {1} ", value, result ); }
// Asynchronous Callback method. public static void MyCallback(IAsyncResult ar) { // Obtains the last parameter of the delegate call. SampSyncSqrDelegate sampDelg = (SampSyncSqrDelegate)ar.get_AsyncState(); // Obtains return value from the delegate call using EndInvoke. AsyncResult aResult = (AsyncResult)ar; SampSyncSqrDelegate temp = (SampSyncSqrDelegate)(aResult.get_AsyncDelegate()); int threadId = AppDomain.GetCurrentThreadId(); int result = temp.EndInvoke(ar); Console.Write("Simple.SomeMethod (AsyncCallback): Result of "); Console.WriteLine("{0} in SampleSynchronized.Square is {1} ", (Int32)value, (Int32)result); } //MyCallback
Imports System Imports System.Threading Imports System.Runtime.Remoting Imports System.Runtime.Remoting.Contexts Imports System.Runtime.Remoting.Messaging ' ' Context-Bound type with Synchronization Context Attribute ' <Synchronization()> Public Class SampleSyncronized Inherits ContextBoundObject ' A method that does some work - returns the square of the given number Public Function Square(i As Integer) As Integer Console.Write("SampleSyncronized.Square called. ") Console.WriteLine("The hash of the current thread is: {0}", Thread.CurrentThread.GetHashCode()) Return i * i End Function 'Square End Class 'SampleSyncronized ' ' Async delegate used to call a method with this signature asynchronously ' Delegate Function SampSyncSqrDelegate(i As Integer) As Integer 'Main sample class Public Class AsyncResultSample Public Shared Sub Main() Dim callParameter As Integer = 0 Dim callResult As Integer = 0 'Create an instance of a context-bound type SampleSynchronized 'Because SampleSynchronized is context-bound, the object sampSyncObj 'is a transparent proxy Dim sampSyncObj As New SampleSyncronized() 'call the method synchronously Console.Write("Making a synchronous call on the object. ") Console.WriteLine("The hash of the current thread is: {0}", Thread.CurrentThread.GetHashCode()) callParameter = 10 callResult = sampSyncObj.Square(callParameter) Console.WriteLine("Result of calling sampSyncObj.Square with {0} is {1}.", callParameter, callResult) Console.WriteLine("") Console.WriteLine("") 'call the method asynchronously Console.Write("Making an asynchronous call on the object. ") Console.WriteLine("The hash of the current thread is: {0}", Thread.CurrentThread.GetHashCode()) Dim sampleDelegate As New SampSyncSqrDelegate(AddressOf sampSyncObj.Square) callParameter = 17 Dim aResult As IAsyncResult = sampleDelegate.BeginInvoke(callParameter, Nothing, Nothing) 'Wait for the call to complete aResult.AsyncWaitHandle.WaitOne() callResult = sampleDelegate.EndInvoke(aResult) Console.WriteLine("Result of calling sampSyncObj.Square with {0} is {1}.", callParameter, callResult) End Sub 'Main End Class 'AsyncResultSample
using System; using System.Threading; using System.Runtime.Remoting; using System.Runtime.Remoting.Contexts; using System.Runtime.Remoting.Messaging; // // Context-Bound type with Synchronization Context Attribute // [Synchronization()] public class SampleSyncronized : ContextBoundObject { // A method that does some work - returns the square of the given number public int Square(int i) { Console.Write("SampleSyncronized.Square called. "); Console.WriteLine("The hash of the current thread is: {0}", Thread.CurrentThread.GetHashCode()); return i*i; } } // // Async delegate used to call a method with this signature asynchronously // public delegate int SampSyncSqrDelegate(int i); //Main sample class public class AsyncResultSample { public static void Main() { int callParameter = 0; int callResult = 0; //Create an instance of a context-bound type SampleSynchronized //Because SampleSynchronized is context-bound, the object sampSyncObj //is a transparent proxy SampleSyncronized sampSyncObj = new SampleSyncronized(); //call the method synchronously Console.Write("Making a synchronous call on the object. "); Console.WriteLine("The hash of the current thread is: {0}", Thread.CurrentThread.GetHashCode()); callParameter = 10; callResult = sampSyncObj.Square(callParameter); Console.WriteLine("Result of calling sampSyncObj.Square with {0} is {1}.\n\n", callParameter, callResult); //call the method asynchronously Console.Write("Making an asynchronous call on the object. "); Console.WriteLine("The hash of the current thread is: {0}", Thread.CurrentThread.GetHashCode()); SampSyncSqrDelegate sampleDelegate = new SampSyncSqrDelegate(sampSyncObj.Square); callParameter = 17; IAsyncResult aResult = sampleDelegate.BeginInvoke(callParameter, null, null); //Wait for the call to complete aResult.AsyncWaitHandle.WaitOne(); callResult = sampleDelegate.EndInvoke(aResult); Console.WriteLine("Result of calling sampSyncObj.Square with {0} is {1}.", callParameter, callResult); } }
using namespace System; using namespace System::Threading; using namespace System::Runtime::Remoting; using namespace System::Runtime::Remoting::Contexts; using namespace System::Runtime::Remoting::Messaging; // // Context-Bound type with Synchronization Context Attribute // public ref class SampleSyncronized: public ContextBoundObject { public: // A method that does some work - returns the square of the given number int Square( int i ) { Console::Write( "SampleSyncronized::Square called. " ); Console::WriteLine( "The hash of the current thread is: {0}", Thread::CurrentThread->GetHashCode() ); return i * i; } }; delegate int SampSyncSqrDelegate( // // Async delegate used to call a method with this signature asynchronously // int i ); //Main sample class int main() { int callParameter = 0; int callResult = 0; //Create an instance of a context-bound type SampleSynchronized //Because SampleSynchronized is context-bound, the Object* sampSyncObj //is a transparent proxy SampleSyncronized^ sampSyncObj = gcnew SampleSyncronized; //call the method synchronously Console::Write( "Making a synchronous call on the Object*. " ); Console::WriteLine( "The hash of the current thread is: {0}", Thread::CurrentThread->GetHashCode() ); callParameter = 10; callResult = sampSyncObj->Square( callParameter ); Console::WriteLine( "Result of calling sampSyncObj.Square with {0} is {1}.\n\n", callParameter, callResult ); //call the method asynchronously Console::Write( "Making an asynchronous call on the Object*. " ); Console::WriteLine( "The hash of the current thread is: {0}", Thread::CurrentThread->GetHashCode() ); SampSyncSqrDelegate^ sampleDelegate = gcnew SampSyncSqrDelegate( sampSyncObj, &SampleSyncronized::Square ); callParameter = 17; IAsyncResult^ aResult = sampleDelegate->BeginInvoke( callParameter, nullptr, 0 ); //Wait for the call to complete aResult->AsyncWaitHandle->WaitOne(); callResult = sampleDelegate->EndInvoke( aResult ); Console::WriteLine( "Result of calling sampSyncObj.Square with {0} is {1}.", callParameter, callResult ); }
Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
開発プラットフォームの中には、.NET Framework によってサポートされていないバージョンがあります。サポートされているバージョンについては、「システム要件」を参照してください。
参照
IAsyncResult プロパティ
IAsyncResult メンバ
- IAsyncResultのページへのリンク