ContainerControl.ActiveControl Property
Gets or sets the active control on the container control.
[Visual Basic] Public Overridable Property ActiveControl As Control Implements _ IContainerControl.ActiveControl [C#] public virtual Control ActiveControl {get; set;} [C++] public: __property virtual Control* get_ActiveControl(); public: __property virtual void set_ActiveControl(Control*); [JScript] public function get ActiveControl() : Control; public function set ActiveControl(Control);
Property Value
The Control that is currently active on the ContainerControl.
Implements
IContainerControl.ActiveControl
Exceptions
| Exception Type | Condition |
|---|---|
| ArgumentException | The Control assigned could not be activated. |
Remarks
This property activates or retrieves the active control on the container control.
Example
[Visual Basic, C#, C++] The following example inherits from the ScrollableControl class and implements the IContainerControl interface. Implementation is added to the ActiveControl property and the ActivateControl method.
[Visual Basic] 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 Get Return Me.myActiveControl End Get Set ' 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. active.Select() Me.ScrollControlIntoView(active) Me.myActiveControl = active Return True End If Return False End Function End Class [C#] using System; using System.Windows.Forms; using System.Drawing; public class MyContainer : ScrollableControl, IContainerControl { private Control activeControl; public MyContainer() { // Make the container control Blue so it can be distinguished on the form. this.BackColor = Color.Blue; // Make the container scrollable. this.AutoScroll = true; } // Add implementation to the IContainerControl.ActiveControl property. public Control ActiveControl { get { return activeControl; } set { // Make sure the control is a member of the ControlCollection. if(this.Controls.Contains(value)) { activeControl = value; } } } // Add implementations to the IContainerControl.ActivateControl(Control) method. public bool ActivateControl(Control active) { if(this.Controls.Contains(active)) { // Select the control and scroll the control into view if needed. active.Select(); this.ScrollControlIntoView(active); this.activeControl = active; return true; } return false; } } [C++] using namespace System; using namespace System::Windows::Forms; using namespace System::Drawing; public __gc class MyContainer : public ScrollableControl, public IContainerControl { private: Control* activeControl; public: MyContainer() { // Make the container control Blue so it can be distinguished on the form. this->BackColor = Color::Blue; // Make the container scrollable. this->AutoScroll = true; } // Add implementation to the IContainerControl.ActiveControl property. __property Control* get_ActiveControl() { return activeControl; } __property void set_ActiveControl(Control* value) { // Make sure the control is a member of the ControlCollection. if (this->Controls->Contains(value)) { activeControl = value; } } // Add implementations to the IContainerControl.ActivateControl(Control) method. bool ActivateControl(Control* active) { if (this->Controls->Contains(active)) { // Select the control and scroll the control into view if needed. active->Select(); this->ScrollControlIntoView(active); this->activeControl = active; return true; } return false; } };
[JScript] No example is available for JScript. To view a Visual Basic, C#, or C++ example, click the Language Filter button
in the upper-left corner of the page.
Requirements
Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family
See Also
ContainerControl Class | ContainerControl Members | System.Windows.Forms Namespace | ScrollableControl | Control