C＃元組。 不包含Item1的定義

Question

class WakeUP
{
    [DllImport("kernel32.dll")]
    public static extern SafeWaitHandle CreateWaitableTimer(IntPtr lpTimerAttributes, 
                                                              bool bManualReset,
                                                            string lpTimerName);

    [DllImport("kernel32.dll", SetLastError = true)]
    [return: MarshalAs(UnmanagedType.Bool)]
    public static extern bool SetWaitableTimer(SafeWaitHandle hTimer, 
                                                [In] ref long pDueTime, 
                                                          int lPeriod,
                                                       IntPtr pfnCompletionRoutine, 
                                                       IntPtr lpArgToCompletionRoutine, 
                                                         bool fResume);

    public event EventHandler Woken;

    private BackgroundWorker bgWorker = new BackgroundWorker();

    public WakeUP()
    {
        bgWorker.DoWork += new DoWorkEventHandler(bgWorker_DoWork);
        bgWorker.RunWorkerCompleted += new RunWorkerCompletedEventHandler(bgWorker_RunWorkerCompleted);
    }

    public void SetWakeUpTime(DateTime time, String tName)
    {
        // Create a 7-tuple. 
        var wutargs = new Tuple<string, string>(time.ToFileTime().ToString(), tName.ToString()); 
        bgWorker.RunWorkerAsync(wutargs);
    }

    void bgWorker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
    {
        if (Woken != null)
        {
            Woken(this, new EventArgs());
        }
    }

    private void bgWorker_DoWork(object sender, DoWorkEventArgs e) 
    {
        var thetuple = e.Argument;
        long wakeuptime = (long)thetuple.Item1;

        using (SafeWaitHandle handle = CreateWaitableTimer(IntPtr.Zero, true, "Timer"))
        {
            //if (SetWaitableTimer(handle, ref "12:00 AM", 0, IntPtr.Zero, IntPtr.Zero, true))
            //{
                //using (EventWaitHandle wh = new EventWaitHandle(false, EventResetMode.AutoReset))
                //{
                    //wh.SafeWaitHandle = handle;
                    //wh.WaitOne();
                //}
            //}
            //else
            //{
                //throw new Win32Exception(Marshal.GetLastWin32Error());
            //}
        }
    }

Visual Studio告訴我有關以下方面的信息：

        long wakeuptime = (long)thetuple.Item1;

錯誤1'對象'不包含'Item1'的定義，並且找不到擴展方法'Item1'接受類型為'object'的第一個參數（您是否缺少using指令或程序集引用？）C：\\ Users \\ esepich \\ Documents \\ Visual Studio 2013 \\ Projects \\ SepysAlarmV1ecs \\ SepysAlarmV1 \\ WakeUP.cs 57 46 SepysAlarmV1

我應該如何訪問元組的元素？

感謝您的發表...

Answer 1

參數可以是任何類型。 它作為object傳遞，因此將其強制轉換回原始類型：

var thetuple = (Tuple<string, string>)e.Argument;

您還將在下一行得到編譯器錯誤：

long wakeuptime = (long)thetuple.Item1;

考慮使用Convert.ToInt64或Int64.TryParse 。