convert from object to ObservableCollection

Hi,

Could anyone help me to convert from object to ObservableCollection, sample code below

func1()

{

lvItems.ItemsSource = portNameLists; //portNameLists is of type ObservableCollection getting assigned to listview object

CollectionView view = (CollectionView)CollectionViewSource.GetDefaultView(lvItems.ItemsSource);

view.Filter = func2;

}

func2(object item)

{

// here i need to convert item which is of type object to ObservableCollection

so that i can perform like

item.Where(X => X.address == addr.Text)

}