ASP.NET

[DefaultProperty("Text")]
[ParseChildren(true), PersistChildren(false)]        

public class MyGrid : GridView
{            
  //... Some variable declarations    
  protected SizeItemCollection _PageSizeItems;    
  [Category("Paging")]            
  [Editor(typeof(CollectionEditor), typeof(System.Drawing.Design.UITypeEditor))]    
  [PersistenceMode(PersistenceMode.InnerDefaultProperty), MergableProperty(false)]    
  [DesignerSerializationVisibility(DesignerSerializationVisibility.Content)]    
  [Description("Items list for the PageSize selector DropDownList")]    
  public SizeItemCollection PageSizeItems    
  {        
    get { return (_PageSizeItems != null ? _PageSizeItems : new SizeItemCollection()); }   
  }    
  protected override void InitializePager(GridViewRow row, int columnSpan, PagedDataSource pagedDataSource)    
  {        
    //Here I create the pager row and added the DropDownList with the values in PageSiZeItems    
  }	    
  //... some more code ...        
}

public class SizeItem : Component
{    
  private int _size;    
  public SizeItem() { }    
  public SizeItem(int size)    
  {        
    _size = size;    
  }    
  public int Size    
  {        
    get { return _size; }
    set { _size = value; }    
  }             
}
public class SizeItemCollection : CollectionBase
{    
  //Here I implemented Add(), Insert(), Remove(), Contains(), IndexOf() and CopyTo()    
  //for my SizeItem class
}