我的事件處理程序永遠不會調用，因爲原始事件在另一個事件處理程序中引發？

Question

儘管在子類中引發了事件，但我的父類中的事件處理程序從不會被調用。

驗證碼：

Public Class childForm 

    Public Event checkboxchangedEvent(ByVal checkbox1 As Boolean, ByVal checkbox2 As Boolean) 
    Private Sub checkboxchanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox1.CheckedChanged, CheckBox2.CheckedChanged 
     RaiseEvent checkboxchangedEvent(CheckBox1.Checked, CheckBox2.Checked) 
     End Sub 
End Class 

Public Class ParentForm 

Friend WithEvents cf As childform = New childform 

Private Sub cf_checkboxchanged(ByVal checkbox1 As Boolean, ByVal checkbox2 As Boolean) Handles cf.checkboxchangedEvent 

     My.Settings.checkbox1 = checkbox1 

     My.Settings.checkbox2 = checkbox2 
    End Sub 

End Class 

Answer 1

你可以試試下面的這個設置事件處理程序的替代方法，

Public Sub ShowChildForm() 
    Dim frm as New childform 
    AddHandler frm.checkboxchangedevent, AddressOf cf_checkboxchanged 
    frm.ShowDialog() 
    RemoveHandler frm.checkboxchangedevent, AddressOf cf_checkboxchanged 
End Sub 

Answer 2

我覺得你的問題是時機。嘗試明確創建表單並在ParentForm的Load事件處理程序中添加處理程序。 （這是所有從內存和未經考驗的這樣事件名稱/簽名爲Load事件類型可能不正確。）

Public Class ParentForm 
    Friend WithEvents cf As childform 

    Private Sub cf_checkboxchanged(ByVal checkbox1 As Boolean, ByVal checkbox2 As Boolean) 
     My.Settings.checkbox1 = checkbox1 
     My.Settings.checkbox2 = checkbox2 
    End Sub 

    Private Sub ParentForm_Load(ByVal sender as object, ByVal e as EventArgs) Handles Me.Load 
     cf = new childForm() 
     AddHandler cf.checkboxchanged, AddressOf cf_checkboxchanged 
     cf.Show() 
    End Sub 
End Class