将UserControl转换为特定类型的用户控件

foreach(UserControl uc in plhMediaBuys.Controls) {
    MyControl c = uc as MyControl;
    if (c != null) {
        c.PublicPropertyIWantAccessTo;
    }
}

foreach(UserControl uc in plhMediaBuys.Controls)
{
  if (uc is MySpecificType)
  {
    return (uc as MySpecificType).PulblicPropertyIWantAccessTo;
  }
}