关于timer控件的1点疑问

2012-07-04

关于timer控件的一点疑问我只想让time_tick里的函数运行一次，我这样做，定义一个全局boolean变量a，初始为tr

关于timer控件的一点疑问
我只想让time_tick里的函数运行一次，我这样做，定义一个全局boolean变量a，初始为true，timer的interval设为10000，也就是10秒，这样写

VB.NET code

 Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick        If a = True Then            MsgBox("safalj")            a = False        End If    End Sub

但结果msgbox还是每隔10秒运行一次啊，我已经将a设为false了，为什么会这样？

[解决办法]
我实在不知道你怎么写的。

VB.NET code

Module Module1    Public a As Boolean = FalseEnd ModulePublic Class Form1    Private Sub Form1_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load        Dim f2 As New Form2        f2.Show()    End Sub    Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click        a = True    End SubEnd ClassPublic Class Form2    Private Sub Timer1_Tick(sender As System.Object, e As System.EventArgs) Handles Timer1.Tick        If a = True Then            MsgBox("safalj")            a = False        End If    End SubEnd Class
[解决办法]
1.  定义静态变量:
 Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
       Static a As Boolean
       My.Application.DoEvents()
       If a = False Then
           a = True
           MsgBox("a")
       End If

   End Sub
2.定义全局变量
就像8楼那样...
楼主基础有待加强

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关于timer控件的1点疑问