每分鐘刷新一次

Question

在表單中有一個標籤。它顯示Web服務是否在每分鐘連接。如何編碼重複這個過程？我會使用線程還是計時器？請分享我。

Answer 1

您需要一個計時器對象才能每X分鐘運行一次代碼。使用單獨的線程來檢查Web服務只需要花費一些時間來檢查並且希望表單在此期間保持響應。

使用計時器非常簡單：

Private WithEvents timer As New System.Timers.Timer 

Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load 
    'Set interval to 1 minute 
    timer.Interval = 60000 

    'Synchronize with current form, or else an error will occur when trying to 
    'update the UI from within the elapsed event 
    timer.SynchronizingObject = Me 
End Sub 


Private Sub timer_Elapsed(ByVal sender As Object, ByVal e As System.Timers.ElapsedEventArgs) Handles timer.Elapsed 
    'Add code here to check if the web service is updated and update label 
End Sub