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namespace Bingosoft.Training2007.CSharp
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{
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delegate int Sum(int num1,int num2);
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/**//// <summary>
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/// 使用Delegate的BeginInvoke方法完成一個函數的異步調用過程。
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/// </summary>
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class Question6
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/**//// <summary>
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/// 求兩個int型數的和(僅供示範)
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/// </summary>
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/// <param name="num1"></param>
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/// <param name="num2"></param>
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/// <returns></returns>
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public static int GetSum(int num1, int num2)
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Thread.Sleep(1000);
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return num1 + num2;
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}
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/// 用EndInvoke等待異步調用
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/// </summary>
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public static void TestAsyn1()
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Sum sum = new Sum(GetSum);
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IAsyncResult result = sum.BeginInvoke(10, 20,null,null);
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Console.WriteLine("計算中
");
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int returnVal = sum.EndInvoke(result);
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Console.WriteLine(returnVal);
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/// 用WaitHandle等待異步調用
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public static void TestAsyn2()
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IAsyncResult result = sum.BeginInvoke(10, 20, null, null);
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result.AsyncWaitHandle.WaitOne();
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Console.WriteLine("計算完畢：");
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/// 輪訓查詢等待異步調用
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public static void TestAsyn3()
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while (!result.IsCompleted)
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Console.WriteLine("計算中
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}
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/// 異步調用完成後，執行回調
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public static void TestAsyn4()
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IAsyncResult result = sum.BeginInvoke(10, 20, new AsyncCallback(Question6.CallBackAsyn), sum);
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/// 回調函數
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/// <param name="ar"></param>
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public static void CallBackAsyn(IAsyncResult ar)
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Sum sum = (Sum)ar.AsyncState;
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int returnVal = sum.EndInvoke(ar);
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MessageBox.Show(returnVal.ToString(), "計算結果:", MessageBoxButtons.OK, MessageBoxIcon.Information);
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}
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}
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}
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//測試Question6
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Question6.TestAsyn1();
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Question6.TestAsyn2();
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Question6.TestAsyn3();
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Question6.TestAsyn4();