See Also: DesignerAttribute Members
The class you use for the design-time services must implement the System.ComponentModel.Design.IDesigner interface.
Use the DesignerAttribute.DesignerBaseTypeName property to find the designer's base type. Use the DesignerAttribute.DesignerTypeName property to get the name of the type of designer associated with this member.
For more information, see Extending Metadata Using Attributes.