c# - Adding a Customized Control To Designer View -

in visual studio (actually 2010, guess goes previous version)
whenever use extended control such :

 public class mainform : form  {     ...     class mylistbox : listbox    {      //my desired behavior    }  } 

i have following error in designer view :

could not find type 'amc.controls.amcstockchart+xchart'. please make sure assembly contains type referenced. if type part of development project, make sure project has been built using settings current platform or cpu.

any workaround appreciated.

ps : not want create user control, place in dll stuff, way work little detail that.

well if want workaround, don't need put custom control in other assembly, long not inner class of form seems work.

of course, you'll need compile current project before being able use through designer.

this works me:

public partial class form1 : form {     public form1()     {         initializecomponent();      }  }  class mylistbox : listbox {  }