Question

我正在尝试创建一个票务柜台，基本上当用户点击按钮即。创建票证，计数器将递增1，直到第二天票证计数器将再次重置为0。

我已将计数器存储在数据库中，因此数据库知道特定用户的最后一个计数器。但是，一旦用户第二天点击按钮，我怎么能将计数器重置为0。我有一个名为checkformidnight的函数，如下所示，但不认为这是正确的方法。

Private Function CreatTicketNumber(ByVal officerId As Integer) As String

    Dim counter As Integer = officer.Officer_Ticket_Counter '' from database
    If IsMidnight(Now) Then
        counter = 0
    Else
        counter = counter + 1
    End If


    Dim TicketNumber As String = counter.ToString("00")

    Return TicketNumber
End Function


Public Function IsMidnight(ByVal value As Date) As Boolean
    Return value.TimeOfDay.Ticks = 0
End Function

Answer 1

在基本模式中，您可以这样做：

1）在设置（例如）中存储应用程序LOAD的日期。这样，您就拥有了当前日期：

    My.Settings.LoadDate = Datetime.Now.Tostring
    My.Settings.Save

2）使用BackgroundWorker并将以下代码放在：

中

Do
  Dim LastDate as datetime = cdate(my.settings.LoadDate)
  if datetime.now.date > LastDate
    Counter = 0
    My.Settings.LoadDate = Datetime.Now.Tostring
    My.Settings.Save
  end if
Sleep(1200)

3）这样，您将有一个不同的线程，每1.2秒检查一次当前日期。如果日期过了今天，您将重置日期设置并重置您的计数器。

4）此代码可能已经过优化，但基本上可以解决您的问题。

Answer 2

定义一个检查DateTime.Now的计时器，每当组件更改时，重置计数器

Dim time As DateTime = DateTime.Now
Dim count = 0L


Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
    'you can use settings to store and restore data
    If File.Exists("date") Then time = DateTime.FromBinary(Long.Parse(File.ReadAllText("date")))
    If File.Exists("count") Then count = Long.Parse(File.ReadAllText("count"))

    Dim t = New Timer
    t.Interval = 1000 ' one second
    t.Enabled = True
    t.Start()


    AddHandler t.Tick, Sub(ss As Object, ee As EventArgs)
                           If DateTime.Now.Day > time.Day Then
                               count = 0
                           End If
                           time = DateTime.Now
                       End Sub
    AddHandler FormClosing, Sub(ss As Object, ee As FormClosingEventArgs)
                                File.WriteAllText("date", time.Ticks.ToString())
                                File.WriteAllText("count", count.ToString())
                            End Sub
End Sub

Answer 3

将DateTime.Today.DayOfWeek值与您的计数器一起存储在表单级别。在Form的Load（）事件中，设置该变量。现在，只要单击按钮，就会检查它并相应地重置：

Public Class Form1

    Private i As Integer = 0
    Private LastDayOfWeek As DayOfWeek

    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles Me.Load
        LastDayOfWeek = DateTime.Today.DayOfWeek
        Label1.Text = i
    End Sub

    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        If DateTime.Today.DayOfWeek = LastDayOfWeek Then
            i = i + 1
        Else
            i = 0
            LastDayOfWeek = DateTime.Today.DayOfWeek
        End If
        Label1.Text = i
    End Sub

End Class

检查第二天

3 个答案: