<PackageReference Include="NETStandard.Library" Version="2.0.2" />

System.Collections.ObjectModel.ReadOnlyObservableCollection<T>

namespace System.Collections.ObjectModel { public class ReadOnlyObservableCollection<T> : ReadOnlyCollection<T>, INotifyCollectionChanged, INotifyPropertyChanged { protected virtual event NotifyCollectionChangedEventHandler CollectionChanged; protected virtual event PropertyChangedEventHandler PropertyChanged; event NotifyCollectionChangedEventHandler INotifyCollectionChanged.CollectionChanged; event PropertyChangedEventHandler INotifyPropertyChanged.PropertyChanged; public ReadOnlyObservableCollection(ObservableCollection<T> list); protected virtual void OnCollectionChanged(NotifyCollectionChangedEventArgs args); protected virtual void OnPropertyChanged(PropertyChangedEventArgs args); } }