How to dock a control with tabbed style into another control through docking context menu in WinForms Docking Manager?

 private void dockingManager1_DockContextMenu(object sender, Syncfusion.Windows.Forms.Tools.DockContextMenuEventArgs arg)
  {
   //Stores the source control
   tempControl=arg.Owner;
    //Get all sibiling controls into the SibilingContolsList array
   this.GetSibilingControls(arg.Owner);
       //flag for whether should add the control into the context menu or not
   bool addThisControl=false;
       //Get collection of currently docked controls under the docking manager
   IEnumerator ienum = this.dockingManager1.Controls;
   ArrayList dockedctrls = new ArrayList();
while(ienum.MoveNext())
    dockedctrls.Add(ienum.Current);
       //Initialize the Parentbar Item
   ParentBarItem DockTabGroup= new ParentBarItem("TabbedWith..");
    //Get the collection of BarItem into the ParenBar Item
   foreach(Control ctrl in dockedctrls)
   {
    addThisControl=true;
    //Checks whether the control is in the current source tabbed group
    foreach(Control control in this.SibilingControlsList)
    {
     if(ctrl==control)
     {
addThisControl=false;
      break;
     }
    }
     //Initializes the baritem and click event for each control
if(addThisControl&&!this.dockingManager1.GetFloatOnly(arg.Owner))
    {
     //We should check the control which is being to add in the ParentbarItem should not same as source control
     //and also it should be visibled control.
     if(ctrl!=arg.Owner && this.dockingManager1.GetDockVisibility(ctrl))
     {
      BarItem panelBar=new BarItem(ctrl.Name);
      panelBar.Click+=new EventHandler(panelBar_Click);
DockTabGroup.Items.Add(panelBar);
     }
    }
   }
    //Added the parent bar Item into the DockContextMenu, if items count is more than 0
   if(DockTabGroup.Items.Count>0)
   {
    //Get the context menu
    PopupMenu menu = arg.ContextMenu;
     //Add the DockTabGroup parent baritem into the DockTo parent baritem
    foreach(BarItem b in menu.ParentBarItem.Items)
    {
     if(b.Text=="Dock to")
     {
      ParentBarItem pb=(ParentBarItem)b;
//Add new parent bar item
pb.Items.Add(DockTabGroup);
     }
    }
}
    //Clear the list of sibiling controls
   this.SibilingControlsList.Clear();
   }
    //This event will trigger when we click on the panel bar
  private void panelBar_Click(object sender, EventArgs e)
  {
       IEnumerator ienum = this.dockingManager1.Controls;
   ArrayList dockedctrls = new ArrayList();
       string CurrentControlName=((BarItem)sender).Text;
while(ienum.MoveNext())
    dockedctrls.Add(ienum.Current);
       //Dock as the tabbed group with the target control
   foreach(Control ctrl in dockedctrls)
   {
if(ctrl.Name==CurrentControlName)
     //Docks a source control into a specified parent control
this.dockingManager1.DockControl(tempControl,ctrl,DockingStyle.Tabbed,ctrl.Width,true);
   }
   }

Private Sub dockingManager1_DockContextMenu(ByVal sender As Object, ByVal arg As Syncfusion.Windows.Forms.Tools.DockContextMenuEventArgs) Handles dockingManager1.DockContextMenu
   'Stores the source control
   tempControl=arg.Owner
    'Get all sibiling controls into the SibilingContolsList array
   Me.GetSibilingControls(arg.Owner)
    'flag for whether should add the control into the context menu or not
   Dim addThisControl As Boolean=False
    'Get collection of currently docked controls under the docking manager
   Dim ienum As IEnumerator = Me.dockingManager1.Controls
   Dim dockedctrls As ArrayList = New ArrayList()
    Do While ienum.MoveNext()
    dockedctrls.Add(ienum.Current)
   Loop
    'Initialize the Parentbar Item
   Dim DockTabGroup As ParentBarItem= New ParentBarItem("TabbedWith..")
    'Get the collection of BarItem into the ParenBar Item
   For Each ctrl As Control In dockedctrls
    addThisControl=True
    'Checks whether the control is in the current source tabbed group
    For Each control As Control In Me.SibilingControlsList
     If ctrl Is control Then
      addThisControl=False
      Exit For
     End If
    Next control
     'Initializes the baritem and click event for each control
    If addThisControl AndAlso (Not Me.dockingManager1.GetFloatOnly(arg.Owner)) Then
     'We should check the control which is being to add in the ParentbarItem should not same as source control
     'and also it should be visibled control.
     If Not ctrl Is arg.Owner AndAlso Me.dockingManager1.GetDockVisibility(ctrl) Then
      Dim panelBar As BarItem = New BarItem(ctrl.Name)
      AddHandler panelBar.Click, AddressOf panelBar_Click
DockTabGroup.Items.Add(panelBar)
     End If
    End If
   Next ctrl
    'Added the parent bar Item into the DockContextMenu, if items count is more than 0
   If DockTabGroup.Items.Count>0 Then
    'Get the context menu
    Dim menu As PopupMenu = arg.ContextMenu
     'Add the DockTabGroup parent baritem into the DockTo parent baritem
    For Each b As BarItem In menu.ParentBarItem.Items
     If b.Text="Dock to" Then
      Dim pb As ParentBarItem=CType(b, ParentBarItem)
       'Add new parent bar item
pb.Items.Add(DockTabGroup)
     End If
    Next b
    End If
    'Clear the list of sibiling controls
   Me.SibilingControlsList.Clear()
   End Sub
    'This event will trigger when we click on the panel bar
  Private Sub panelBar_Click(ByVal sender As Object, ByVal e As EventArgs)
    Dim ienum As IEnumerator = Me.dockingManager1.Controls
   Dim dockedctrls As ArrayList = New ArrayList()
    Dim CurrentControlName As String=(CType(sender, BarItem)).Text
    Do While ienum.MoveNext()
    dockedctrls.Add(ienum.Current)
   Loop
    'Dock as the tabbed group with the target control
   For Each ctrl As Control In dockedctrls
    If ctrl.Name=CurrentControlName Then
     'Docks a source control into a specified parent control
Me.dockingManager1.DockControl(tempControl,ctrl,DockingStyle.Tabbed,ctrl.Width,True)
    End If
   Next ctrl
   End Sub

//Collects the list of sibiling controls connected with the source control
public void GetSibilingControls(Control ctrl)
{
   //Host form created by list box parent control
   Syncfusion.Windows.Forms.Tools.DockHost dhost = ctrl.Parent as Syncfusion.Windows.Forms.Tools.DockHost;
   Syncfusion.Windows.Forms.Tools.DockHostController dhc = dhost.InternalController as Syncfusion.Windows.Forms.Tools.DockHostController;
    //This statement checks whether the control within the tab control or not
   if(dhc.ParentController is Syncfusion.Windows.Forms.Tools.DockTabController)
   {
       Syncfusion.Windows.Forms.Tools.DockTabControl docktab = (dhc.ParentController as Syncfusion.Windows.Forms.Tools.DockTabController).TabControl;
       //Here the code will add the list of child control which are grouped with the source control.
       foreach(Syncfusion.Windows.Forms.Tools.DockTabPage tabpage in docktab.TabPages)
       {
          this.SibilingControlsList.Add( tabpage.dhcClient.HostControl.Controls[0]);
       }
   }
}

'Collects the list of sibiling controls connected with the source control
 'Collects the list of sibiling controls connected with the source control
 Public Sub GetSibilingControls(ByVal ctrl As Control)
    'Host form created by list box parent control
    Dim dhost As Syncfusion.Windows.Forms.Tools.DockHost = CType(ctrl.Parent, Syncfusion.Windows.Forms.Tools.DockHost)
    Dim dhc As Syncfusion.Windows.Forms.Tools.DockHostController = CType(dhost.InternalController, Syncfusion.Windows.Forms.Tools.DockHostController)
    'This statement checks whether the control within the tab control or not
    If TypeOf dhc.ParentController Is Syncfusion.Windows.Forms.Tools.DockTabController Then
       Dim docktab As Syncfusion.Windows.Forms.Tools.DockTabControl = CType(dhc.ParentController, Syncfusion.Windows.Forms.Tools.DockTabController).TabControl
       'Here the code will add the list of child control which are grouped with the source control.
       For Each tabpage As Syncfusion.Windows.Forms.Tools.DockTabPage In docktab.TabPages
           Me.SibilingControlsList.Add(tabpage.dhcClient.HostControl.Controls(0))
       Next tabpage
    End If
 End Sub