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ControlEventArgs Class

Provides data for the ControlAdded and ControlRemoved events.

For a list of all members of this type, see ControlEventArgs Members.

System.Object
   System.EventArgs
      System.Windows.Forms.ControlEventArgs

[Visual Basic]
Public Class ControlEventArgs
   Inherits EventArgs
[C#]
public class ControlEventArgs : EventArgs
[C++]
public __gc class ControlEventArgs : public EventArgs
[JScript]
public class ControlEventArgs extends EventArgs

Thread Safety

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Remarks

For more information about handling events, see Consuming Events.

Example

[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 handling 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 handling 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 handling methods.
private void Form1_Load(object sender, System.EventArgs e)
{
    // Connect the ControlRemoved and ControlAdded event handlers
    // to the event handling 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 handling methods.
private:
void Form1_Load(Object* /*sender*/, System::EventArgs* /*e*/)
{
   // Connect the ControlRemoved and ControlAdded event handlers
   // to the event handling methods.
   // ControlRemoved and ControlAdded are not available at design time.
   this->ControlRemoved += new System::Windows::Forms::ControlEventHandler(this, &Form1::Control_Removed);
   this->ControlAdded += new System::Windows::Forms::ControlEventHandler(this, &Form1::Control_Added);
}

void Control_Added(Object* /*sender*/, System::Windows::Forms::ControlEventArgs* e)
{
   MessageBox::Show(String::Format( S"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( S"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 = new 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 = S"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 = __try_cast<Control*>(myEnum->Current);
      // Determine whether the control is textBox1,
      // and if it is, remove it.
      if (tempCtrl->Name->Equals(S"textBox1"))
      {
         this->Controls->Remove(tempCtrl);
      }
   }
}

[JScript] No example is available for JScript. To view a Visual Basic, C#, or C++ example, click the Language Filter button Language Filter in the upper-left corner of the page.

Requirements

Namespace: System.Windows.Forms

Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family

Assembly: System.Windows.Forms (in System.Windows.Forms.dll)

See Also

ControlEventArgs Members | System.Windows.Forms Namespace | ControlEventHandler | ControlAdded | ControlRemoved

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