Hi Stelios,
Docking control can be closed using the method DockingManager.SetDockVisibility ( control , false ).
this.DockingManager1.SetDockVisibility ( this.Panel1 , false );
When the docking control is closed, It can''t be disposed because it can be made visible whenever we need the control using the same method with different values.
this.DockingManager1.SetDockVisibility( this.Panel1 , true );
Herewith I have attached the sample for your reference. Please go through the sample and let me know if you have any other issues.
Sample
Thanks for using Syncfusion products.
Regards,
Murugan P.S