Question

我有以下代码; 我添加了第二个表单并以编程方式控制它，但计时器在第二个表单中无法正常工作; 当然它以主要形式正常运作; 在第二种形式中，我需要帮助，就像我在主要形式中所做的一样; 提前感谢您的帮助;

Public Class Form1
    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        Dim frmNew As New Form
        frmNew.Visible = True
        Dim Label2 As New Label()
        frmNew.Controls.Add(Label2)
        Label2.Name = "Label1"
        oTimer = New System.Windows.Forms.Timer
        oTimer.Interval = 1000
        oTimer.Enabled = True
        oTimer.Start()
        frmNew.Text = Date.Now
        Label2.Text = Date.Now
    End Sub
    Private WithEvents oTimer As System.Windows.Forms.Timer
    Private Sub timerTicks() Handles oTimer.Tick
        Me.Text = Date.Now
        label1.text = Date.Now
        'frmNew.Text = Date.Now
        'frmNew.Label2.Text = Date.Now
    End Sub
    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
    End Sub
End Class

Answer 1

您需要以某种方式将对Form和Label的引用传递给Timer的Tick（）事件。这是一种方法：

Public Class Form1

    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        Dim frmNew As New Form
        Dim Label2 As New Label()
        frmNew.Controls.Add(Label2)
        Dim tmr As New System.Windows.Forms.Timer
        AddHandler tmr.Tick, AddressOf tmr_Tick
        tmr.Tag = New Tuple(Of Control, Control)(frmNew, Label2)
        tmr.Interval = 1000
        tmr.Start()
        frmNew.Text = Date.Now
        Label2.Text = Date.Now
        frmNew.Show()
    End Sub

    Private Sub tmr_Tick(sender As Object, e As EventArgs)
        Dim T As Tuple(Of Control, Control) = DirectCast(DirectCast(sender, System.Windows.Forms.Timer).Tag, Tuple(Of Control, Control))
        Dim frm As Form = DirectCast(T.Item1, Form)
        Dim lbl As Label = DirectCast(T.Item2, Label)
        Dim curTime As String = DateTime.Now.ToString("h:mm:ss tt")
        frm.Text = curTime
        lbl.Text = curTime
    End Sub

End Class

以编程方式添加表单和控件

1 个答案: