余小章 @ 大內殿堂

1.當控制項建立時就會依建立事項一一產生對應的順序

http://msdn.microsoft.com/zh-tw/library/86faxx0d.aspx

啟動時

• Control.HandleCreated
  發生於為控制項建立控制代碼時。

• Control.BindingContextChanged
  發生於 BindingContext 屬性的值變更時。

• Form.Load
  發生在表單第一次顯示之前。

• Control.VisibleChanged
  發生於 Visible 屬性值變更時。

• Form.Activated
  發生於表單以程式碼或由使用者啟動時。

• Form.Shown
  每當第一次顯示表單時發生。

'啟動事件順序
Private Sub Form1_HandleCreated(ByVal sender As Object, ByVal e As EventArgs) Handles MyBase.HandleCreated
    Console.WriteLine(Date.Now & "-----> 1.Form1_HandleCreated")
End Sub
Private Sub Form1_BindingContextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.BindingContextChanged
    Console.WriteLine(Date.Now & "-----> 2.Form1_BindingContextChanged")
End Sub
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
    Console.WriteLine(Date.Now & "-----> 3.Form1_Load")
End Sub
Private Sub Form1_VisibleChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.VisibleChanged
    Console.WriteLine(Date.Now & "-----> 4.Form1_VisibleChanged")
End Sub
Private Sub Form1_Activated(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Activated
    Console.WriteLine(Date.Now & "-----> 5.Form1_Activated")
End Sub
Private Sub Form1_Shown(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Shown
    Console.WriteLine(Date.Now & "-----> 6.Form1_Shown")
End Sub

 

關閉時

• Form.Closing
  發生於表單正在關閉時。

• Form.FormClosing
  發生於表單關閉之前。

• Form.Closed
  發生於表單已關閉時。

• Form.FormClosed
  發生於表單關閉之後。

• Form.Deactivate
  發生於表單失去焦點且不再是使用中的表單時。

• Application 類別的 ApplicationExit 事件會在主要表單的關閉事件之後引發。

'關閉事件順序
Private Sub Form1_Closing(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Closing
    Console.WriteLine(Date.Now & "-----> 1.Form1_Closing")
End Sub
Private Sub Form1_FormClosing(ByVal sender As System.Object, ByVal e As System.Windows.Forms.FormClosingEventArgs) Handles MyBase.FormClosing
    Console.WriteLine(Date.Now & "-----> 2.Form1_FormClosing")
End Sub
Private Sub Form1_Closed(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Closed
    Console.WriteLine(Date.Now & "-----> 3.Form1_Closed")
End Sub 

Private Sub Form1_FormClosed(ByVal sender As System.Object, ByVal e As System.Windows.Forms.FormClosedEventArgs) Handles MyBase.FormClosed
    Console.WriteLine(Date.Now & "-----> 4.Form1_FormClosed")
End Sub 

Private Sub Form1_Deactivate(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Deactivate
    Console.WriteLine(Date.Now & "-----> 5.Form1_Deactivate")
End Sub 

 

  
  
  
 
  
  
  
 
  
  
  
  
Private Sub Form1_Closing(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Closing
    '實作內容
End Sub
 
   
 
  
this.Closing += new System.ComponentModel.CancelEventHandler(this.Form1_Closing);

但，我們怎麼知道該如何註冊事件Handler？要用什麼Handler？要用什麼方法傳遞委派？現在來說明一下，假設在MSDN看到以下說明範例：
  
private void Form1_Closing(object sender, System.ComponentModel.CancelEventArgs e)
{
//實作內容
}
 
   
 
System.ComponentModel.CancelEventArgs，是傳遞參數，所以我們需要一個事件的Handler，它就是：
System.ComponentModel.CancelEventHandler ，所以我們採用它來委派事件。 



Form1_Closing，是方法的名稱，方法傳遞。是跟Handler說要傳遞什麼方法。
所以當看到private void Form1_Closing(object sender, System.ComponentModel.CancelEventArgs e)
就表示Form1_Closing是委派的傳遞方法

  
  

    
  
 
   
    
 
  

 
 
   
OnHandleCreated 
    
OnBindingContextChanged
    
OnLoad 
    
OnVisibleChanged 
    
OnActivated 
    
OnShown 
 
    
關閉
  
   
OnClosing
    
OnFormClosing
    
OnClosed
    
OnFormClosed
    
OnDeactivate
 
  
 使用覆寫即可觸發 Form.Load 事件並把原本的 Form.Load 事件給覆寫掉
    
Protected Overrides Sub OnLoad(ByVal e As EventArgs)
    Console.WriteLine(Date.Now & "-----> 3.OnLoad")
End Sub
  
  

   
 5.有幾個已經過時的東西，就儘量鼻要再用它們了吧。(難怪在C#的Snippet 看不到它們倆)
  
Closing 事件在 .NET Framework 2.0 中已過時，請改用 FormClosing 事件。
  
Closed 事件在 .NET Framework 2.0 中已過時，請改用 FormClosed 事件。
  
 
  
6.如何將視窗關閉後最小化
  
利用剛剛所學覆寫 OnFormClosing 方法即可
  
VB
  
Protected Overrides Sub OnFormClosing(ByVal e As FormClosingEventArgs)
    e.Cancel = True
    Me.WindowState = System.Windows.Forms.FormWindowState.Minimized
End Sub
  

 
  
C#
  
protected override void OnFormClosing(FormClosingEventArgs e)//重載關閉函數
{
    e.Cancel = true;
    this.WindowState = System.Windows.Forms.FormWindowState.Minimized; 
}
  
7.範例下載：
  
CS_EventOder.rar
  
VB_EventOder.rar
 
 
 
 
                    
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Microsoft MVP Award 2010~2017 C# 第四季
Microsoft MVP Award 2018~2022 .NET