IContainerControl.ActiveControl Property


Gets or sets the control that is active on the container control.

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

Property ActiveControl As Control

Property Value

Type: System.Windows.Forms.Control

The Control that is currently active on the container control.

Notes to Implementers:

When implemented in a class, this property activates or retrieves the active control on the container control.

The following example inherits from the ScrollableControl class and implements the IContainerControl interface. Implementation is added to the ActiveControl property and the ActivateControl method.

Imports System
Imports System.Windows.Forms
Imports System.Drawing

   Public Class MyContainerControl
      Inherits ScrollableControl
      Implements IContainerControl 

      Private myActiveControl As Control

      Public Sub New()
         ' Make the container control Blue so it can be distinguished on the form.
         Me.BackColor = Color.Blue

         ' Make the container scrollable.
         Me.AutoScroll = True
      End Sub 

      ' Add implementation to the IContainerControl.ActiveControl property.
      Public Property ActiveControl() As Control Implements IContainerControl.ActiveControl
            Return Me.myActiveControl
         End Get

            ' Make sure the control is a member of the ControlCollection.
            If Me.Controls.Contains(value) Then
               Me.myActiveControl = value
            End If
         End Set
      End Property

      ' Add implementation to the IContainerControl.ActivateControl(Control) method.
      public Function ActivateControl(active As Control) As Boolean Implements IContainerControl.ActivateControl
         If Me.Controls.Contains(active) Then
            ' Select the control and scroll the control into view if needed.
            Me.myActiveControl = active
            Return True
         End If
         Return False
      End Function 

   End Class  

.NET Framework
Available since 1.1
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