Question

我对C＃很新，我正在使用Modified WPF应用程序。我的程序的问题是循环是无限的...... 虽然（现在＆lt; end）没有在结束时结束，但它仍然会继续，直到你终止主进程。该节目正在播放电影和图片，因此每次都不同。这意味着now = now.AddSeconds不起作用。正确？

startupinfo = Listbox

    private bool startjob() //DateTime checking for DateValue and start's if correct value.
    {
        DateTime? start = DateTimePicker1.Value;
        DateTime? end = DateTimePicker2.Value;
        DateTime now = DateTime.Now;

        if (start == null || end == null)
        {
            Xceed.Wpf.Toolkit.MessageBox.Show("one of the pickers is empty");
        }
        else if (now >= start.Value && now <= end.Value)
        {
            while (now < end)
            {
                foreach (var selected in startupinfo.SelectedItems)
                {
                    string s = selected.ToString();

                    if (startupinfoDict.ContainsKey(s))
                    {

                        Process process = Process.Start(startupinfoDict[s]);
                        process.WaitForExit();
                        while (!process.HasExited)
                            Thread.Sleep(500);
                    }
                }
                foreach (var selected in listBox2.SelectedItems)
                {
                    string s = selected.ToString();

                    if (listBox2Dict.ContainsKey(s))
                    {
                        Process process = Process.Start(listBox2Dict[s]);
                        process.WaitForExit();
                        while (!process.HasExited)
                            Thread.Sleep(500);
                    }
                }
            }
            return true;
        }
        return false;
    }

Answer 1

你永远不会在循环中重新评估“现在”。

Answer 2

您没有在循环中修改now的值。它始终会将now < end评估为True。因此无限循环

Answer 3

now变量的值永远不会改变。你可以用这种方式循环：

while (DateTime.Now < end.Value)

虽然（现在＆lt; end）没有在结束时结束它仍然在无限循环中继续？

3 个答案: