C#

public bool EmailValid(string email)
{
    string _expression = @"^([a-zA-Z0-9_\-\.]+)@((\[[0-9]{1,3}" +
        @"\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([a-zA-Z0-9\-]+\" +
        @".)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\]?)$";

    return System.Text.RegularExpressions.Regex.IsMatch( email, _expression );
}

PropertyDescriptorCollection pdcoldControl = TypeDescriptor.GetProperties(oldControl);
PropertyDescriptorCollection pdcnewControl = TypeDescriptor.GetProperties(newControl);
 
foreach(PropertyDescriptor pdoldControl in pdcoldControl)
{ //Here you should define some rules like this:
  if((pdoldControl.Attributes.Contains(CategoryAttribute.Appearance) && pdoldControl.IsBrowsable)
  || (pdoldControl.Attributes.Contains(CategoryAttribute.Behavior) && pdoldControl.IsBrowsable && pdoldControl.IsReadOnly==false))
  {
    PropertyDescriptor pdnewControl = pdcnewControl[pdoldControl.Name];
    pdnewControl.SetValue(newControl,pdoldControl.GetValue(oldControl));
  }
}
TypeDescriptor.Refresh(oldControl);
TypeDescriptor.Refresh(newControl);
 
//set some additional properties, like this:
newControl.Size = oldControl.Size;
newControl.Text = oldControl.Text;

Mark Nischalke wrote:

You don't need to use new with value types