Hi.
This time you must implement type converter to help serializer to  render
the code..

 [TypeConverter(typeof(MyObjectConverter))]
// Declare converter attirbute
 public class MyOBject
 {
  string _name;
// This is for constructor with values
  public MyOBject(string name )
  {
   _name = name;
  }
// Default contructor for collection editor
  public MyOBject()
  {
   _name = "";
  }
  public string Name
  {
   get
   {
    return _name;
   }
   set
   {
    _name = value;
   }
  }
 }
 public class MyObjectConverter:TypeConverter
 {
  public override bool CanConvertTo(ITypeDescriptorContext context, Type
destinationType)
  {
   if(destinationType ==
typeof(System.ComponentModel.Design.Serialization.InstanceDescriptor))
    return true;
   return base.CanConvertTo (context, destinationType);
  }
  public override object ConvertTo(ITypeDescriptorContext context,
System.Globalization.CultureInfo culture, object value, Type
destinationType)
  {
   if(destinationType ==
typeof(System.ComponentModel.Design.Serialization.InstanceDescriptor))
   {
    MyOBject val = (value as MyOBject);
    System.Reflection.ConstructorInfo ci =        typeof(
MyOBject).GetConstructor(new Type  [] {typeof( string) });
    if(ci !=null)
     return new
System.ComponentModel.Design.Serialization.InstanceDescriptor(ci,new
object[] {val.Name});
   }
   return base.ConvertTo (context, culture, value, destinationType);
  }
 }

 public class MyObjectCollection:CollectionBase
 {
  public MyOBject this[ int index ]
  {
   get
   {
    return( (MyOBject) List[index] );
   }
   set
   {
    List[index] = value;
   }
  }

  public int Add( MyOBject value )
  {
   return( List.Add( value ) );
  }

  public int IndexOf( MyOBject value )
  {
   return( List.IndexOf( value ) );
  }

  public void Insert( int index, MyOBject value )
  {
   List.Insert( index, value );
  }

  public void Remove( MyOBject value )
  {
   List.Remove( value );
  }

  public bool Contains( MyOBject value )
  {
   return( List.Contains( value ) );
  }
 }

 MyObjectCollection _objects = new MyObjectCollection();
  [DesignerSerializationVisibility(DesignerSerializationVisibility.Content)]
 public MyObjectCollection Objects
 {
  get
  {
   return _objects;
  }
  set
  {
   _objects = value;
  }
 }
----- Original Message -----
From: "frankk" <frank@aspdb.com>
Newsgroups: microsoft.public.dotnet.framework.windowsforms.designtime
Sent: Tuesday, April 05, 2005 6:14 AM
Subject: Re: How to build a Design Time PropertyGrid