Control.OnControlRemoved メソッド

.NET Framework クラス ライブラリ リファレンス

Control.OnControlRemoved メソッド

ControlRemoved イベントを発生させます。

名前空間: System.Windows.Forms
アセンブリ: System.Windows.Forms (system.windows.forms.dll 内)
構文

Visual Basic (宣言)

Protected Overridable Sub
 OnControlRemoved ( _
    e As ControlEventArgs _
)

Visual Basic (使用法)

Dim e As ControlEventArgs

Me.OnControlRemoved(e)

C#

protected virtual void OnControlRemoved (
    ControlEventArgs e
)

C++

protected:
virtual void OnControlRemoved (
    ControlEventArgs^ e
)

J#

protected void OnControlRemoved (
    ControlEventArgs e
)

JScript

protected function OnControlRemoved (
    e : ControlEventArgs
)

パラメータ

e

イベント データを格納している ControlEventArgs。

解説

コントロールから子コントロールが削除されるときに呼び出されます。

イベントが発生すると、デリゲートを使用してイベント ハンドラが呼び出されます。詳細については、「イベントの発生」を参照してください。

OnControlRemoved メソッドを使用すると、デリゲートを結び付けずに、派生クラスでイベントを処理することもできます。派生クラスでイベントを処理する場合は、この手法をお勧めします。

継承時の注意 派生クラスで OnControlRemoved をオーバーライドする場合は、登録されているデリゲートがイベントを受け取ることができるように、基本クラスの OnControlRemoved メソッドを呼び出してください。

使用例

ControlRemoved を使用して、フォームからコントロールを削除し、削除されたコントロールの名前を MessageBox に表示するコード例を次に示します。

Visual Basic

' This example demonstrates the use of the ControlAdded and
' ControlRemoved events. This example assumes that two Button controls
 
' are added to the form and connected to the addControl_Click and 
' removeControl_Click event-handler methods.
Private Sub Form1_Load(ByVal
 sender As Object, ByVal
 e As System.EventArgs) Handles MyBase.Load
    ' Connect the ControlRemoved and ControlAdded event handlers to
 the event-handler methods.
    ' ControlRemoved and ControlAdded are not available at design time.
    AddHandler Me.ControlRemoved, AddressOf
 Me.Control_Removed
    AddHandler Me.ControlAdded, AddressOf
 Me.Control_Added
End Sub 'Form1_Load


Private Sub Control_Added(ByVal
 sender As Object, ByVal
 e As System.Windows.Forms.ControlEventArgs)
    MessageBox.Show(("The control named " + e.Control.Name
 + " has been added to the form."))
End Sub


Private Sub Control_Removed(ByVal
 sender As Object, ByVal
 e As System.Windows.Forms.ControlEventArgs)
    MessageBox.Show(("The control named " + e.Control.Name
 + " has been removed from the form."))
End Sub


' Click event handler for a Button control. Adds a TextBox to the form.
Private Sub addControl_Click(ByVal
 sender As Object, ByVal
 e As System.EventArgs) Handles button1.Click
    ' Create a new TextBox control and add it to the form.
    Dim textBox1 As New
 TextBox()
    textBox1.Size = New Size(100, 10)
    textBox1.Location = New Point(10, 10)
    ' Name the control in order to remove it later. 
    ' The name must be specified if a control is added at run time.
    textBox1.Name = "textBox1"

    ' Add the control to the form's control collection.
    Me.Controls.Add(textBox1)
End Sub


' Click event handler for a Button control.
' Removes the previously added TextBox from the form.
Private Sub removeControl_Click(ByVal
 sender As Object, ByVal
 e As System.EventArgs) Handles button2.Click
    ' Loop through all controls in the form's control collection.
    Dim tempCtrl As Control
    For Each tempCtrl In
 Me.Controls
        ' Determine whether the control is textBox1,
        ' and if it is, remove it.
        If tempCtrl.Name = "textBox1"
 Then
            Me.Controls.Remove(tempCtrl)
        End If
    Next tempCtrl
End Sub

C#

// This example demonstrates the use of the ControlAdded and
// ControlRemoved events. This example assumes that two Button controls
// are added to the form and connected to the addControl_Click and
// removeControl_Click event-handler methods.
private void Form1_Load(object sender, System.EventArgs
 e)
{
    // Connect the ControlRemoved and ControlAdded event handlers
    // to the event-handler methods.
    // ControlRemoved and ControlAdded are not available at design time.
    this.ControlRemoved += new System.Windows.Forms.ControlEventHandler(this.Control_Removed);
    this.ControlAdded += new System.Windows.Forms.ControlEventHandler(this.Control_Added);
}

private void Control_Added(object sender, System.Windows.Forms.ControlEventArgs
 e)
{
    MessageBox.Show("The control named " + e.Control.Name + " has
 been added to the form.");
}

private void Control_Removed(object sender,
 System.Windows.Forms.ControlEventArgs e)
{
    MessageBox.Show("The control named " + e.Control.Name + " has
 been removed from the form.");
}

// Click event handler for a Button control. Adds a TextBox to the form.
private void addControl_Click(object sender,
 System.EventArgs e)
{
    // Create a new TextBox control and add it to the form.
    TextBox textBox1 = new TextBox();
    textBox1.Size = new Size(100,10);
    textBox1.Location = new Point(10,10);
    // Name the control in order to remove it later. The name must be
 specified
    // if a control is added at run time.
    textBox1.Name = "textBox1";

    // Add the control to the form's control collection.
    this.Controls.Add(textBox1);
}

// Click event handler for a Button control.
// Removes the previously added TextBox from the form.
private void removeControl_Click(object sender,
 System.EventArgs e)
{
    // Loop through all controls in the form's control collection.
    foreach (Control tempCtrl in this.Controls)
    {
        // Determine whether the control is textBox1,
        // and if it is, remove it.
        if (tempCtrl.Name == "textBox1")
        {
            this.Controls.Remove(tempCtrl);
        }
    }
}

C++

   // This example demonstrates the use of the ControlAdded and
   // ControlRemoved events. This example assumes that two Button controls
   // are added to the form and connected to the addControl_Click and
   // removeControl_Click event-handler methods.
private:
   void Form1_Load( Object^ /*sender*/, System::EventArgs^ /*e*/
 )
   {
      // Connect the ControlRemoved and ControlAdded event handlers
      // to the event-handler methods.
      // ControlRemoved and ControlAdded are not available at design
 time.
      this->ControlRemoved += gcnew System::Windows::Forms::ControlEventHandler(
 this, &Form1::Control_Removed );
      this->ControlAdded += gcnew System::Windows::Forms::ControlEventHandler(
 this, &Form1::Control_Added );
   }

   void Control_Added( Object^ /*sender*/, System::Windows::Forms::ControlEventArgs^
 e )
   {
      MessageBox::Show( String::Format( "The control named {0} has been added
 to the form.", e->Control->Name ) );
   }

   void Control_Removed( Object^ /*sender*/, System::Windows::Forms::ControlEventArgs^
 e )
   {
      MessageBox::Show( String::Format( "The control named {0} has been removed
 from the form.", e->Control->Name ) );
   }

   // Click event handler for a Button control. Adds a TextBox to the
 form.
   void addControl_Click( Object^ /*sender*/, System::EventArgs^
 /*e*/ )
   {
      // Create a new TextBox control and add it to the form.
      TextBox^ textBox1 = gcnew TextBox;
      textBox1->Size = System::Drawing::Size( 100, 10 );
      textBox1->Location = Point(10,10);

      // Name the control in order to remove it later. The name must be
 specified
      // if a control is added at run time.
      textBox1->Name = "textBox1";

      // Add the control to the form's control collection.
      this->Controls->Add( textBox1 );
   }

   // Click event handler for a Button control.
   // Removes the previously added TextBox from the form.
   void removeControl_Click( Object^ /*sender*/, System::EventArgs^
 /*e*/ )
   {
      // Loop through all controls in the form's control collection.
      IEnumerator^ myEnum = this->Controls->GetEnumerator();
      while ( myEnum->MoveNext() )
      {
         Control^ tempCtrl = safe_cast<Control^>(myEnum->Current);
         
         // Determine whether the control is textBox1,
         // and if it is, remove it.
         if ( tempCtrl->Name->Equals( "textBox1"
 ) )
         {
            this->Controls->Remove( tempCtrl );
         }
      }
   }

J#

// This example demonstrates the use of the ControlAdded and
// ControlRemoved events. This example assumes that two Button controls
// are added to the form and connected to the addControl_Click and
// removeControl_Click event-handler methods.
private void Form1_Load(Object sender, System.EventArgs
 e)
{
    // Connect the ControlRemoved and ControlAdded event handlers
    // to the event-handler methods.
    // ControlRemoved and ControlAdded are not available at design time.
    this.add_ControlRemoved(new System.Windows.Forms.
        ControlEventHandler(this.Control_Removed));
    this.add_ControlAdded(new System.Windows.Forms.
        ControlEventHandler(this.Control_Added));
} //Form1_Load

private void Control_Added(Object sender, System.Windows.Forms.
    ControlEventArgs e)
{
    MessageBox.Show("The control named " + e.get_Control().get_Name() 
        + " has been added to the form.");
} //Control_Added

private void Control_Removed(Object sender,
 System.Windows.Forms.
    ControlEventArgs e)
{
    MessageBox.Show("The control named " + e.get_Control().get_Name() 
        + " has been removed from the form.");
} //Control_Removed

// Click event handler for a Button control. Adds a TextBox to the form.
private void addControl_Click(Object sender,
 System.EventArgs e)
{
    // Create a new TextBox control and add it to the form.
    TextBox textBox1 = new TextBox();
    textBox1.set_Size(new Size(100, 10));
    textBox1.set_Location(new Point(10, 10));

    // Name the control in order to remove it later. 
    // The name must be specified
    // if a control is added at run time.
    textBox1.set_Name("textBox1");

    // Add the control to the form's control collection.
    this.get_Controls().Add(textBox1);
} //addControl_Click

// Click event handler for a Button control.
// Removes the previously added TextBox from the form.
private void removeControl_Click(Object sender,
 System.EventArgs e)
{
    // Loop through all controls in the form's control collection.
    for (int iCtr = 0; iCtr < this.get_Controls().get_Count();
 iCtr++) {
        Control tempCtrl = this.get_Controls().get_Item(iCtr);
        
        // Determine whether the control is textBox1,
        // and if it is, remove it.
        if (tempCtrl.get_Name().Equals("textBox1"))
 {
            this.get_Controls().Remove(tempCtrl);
        }
    }
} //removeControl_Click

プラットフォーム

Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

開発プラットフォームの中には、.NET Framework によってサポートされていないバージョンがあります。サポートされているバージョンについては、「システム要件」を参照してください。

バージョン情報

.NET Framework
サポート対象 : 2.0、1.1、1.0

参照

関連項目
Control クラス
Control メンバ
System.Windows.Forms 名前空間
ControlRemoved