casting problems

• • Reply

  17 years ago

  by Oculus

  Oculus

  , United States

  Joined 17 years ago

  Hi !
  

  
  I hope somebody can help me, i'm completly out of mind.
  My problem:
  

  
  I have a class inherited from Windows.Forms.Control named BasicModule, which implements an interface named IModule (this has nothing to do with the Module-Class of the framework. it's selfmade).
  

  
  Now when I instantiate an object dynamically from an assembly created from the source of BasicModule, i'm able to cast this object to Control, but not to IModule, not even to BasicModule.
  

  
  so that you can imagine something:
  

  
  public class BasicModule : Control, IModule
  { ... }
  

  
  public interface IModule
  { ... }
  

  
  now the critical part:
  

  
  ModuleEntity selected = (ModuleEntity)trvQueries.SelectedNode.Tag;
  object instance = selected.Library.CreateInstance("DAP." + selected.Description.Class,true);
  pnlModule.Controls.Add((Control)instance);
  ((IModule)instance).DBConnection = dbConnection;
  

  
  ModuleEntity holds information about the loaded assembly (stored in member "Library", "DAP" is namespace of project)
  pnlModule is a panel to which i want to add the control
  

  
  it just doesn't work !
  the debugger even tells me, that "instance" is of type BasicModule, but i'm not able to cast it to this class
  

  
  

  
  i also tried to make a abstract base-class, which inherits Controls and implements IModule
  and inherit BasicModule from this base-class
  but i also can't cast to that abstract base-class !
  

  
  i'm freaking out
  

  
  please help me, i'm in serious trouble if i don't solve the problem soon
  

  
  

  
  ps: it's an requirement, that i can load any assembly-class, which implements the IModule interface, at runtime
  this is the base of an extensible application which loads specific dlls described in some xml-configuration-file
  so you don't have to rebuild the application when adding new modules

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