如何创建Generic StateManagedCollection？

public class StateManagedCollection<T> : IList<T>, INotifyPropertyChanged, INotifyCollectionChanged
{
    private readonly IList<T> _internalList;

    public StateManagedCollection()
    {
        _internalList = new List<T>();
    }

    public StateManagedCollection(IEnumerable<T> items)
    {
        _internalList = new List<T>(items);
    }

    public event PropertyChangedEventHandler PropertyChanged;
    public event NotifyCollectionChangedEventHandler CollectionChanged;

    public T this[int index]
    {
        get => _internalList[index];
        set
        {
            _internalList[index] = value;
            OnPropertyChanged(new PropertyChangedEventArgs(nameof(Item[])));
            OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Replace, value, index));
        }
    }

    public int Count => _internalList.Count;

    public bool IsReadOnly => _internalList.IsReadOnly;

    public void Add(T item)
    {
        _internalList.Add(item);
        OnPropertyChanged(new PropertyChangedEventArgs(nameof(Count)));
        OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Add, item, _internalList.IndexOf(item)));
    }

    public void Clear()
    {
        _internalList.Clear();
        OnPropertyChanged(new PropertyChangedEventArgs(nameof(Count)));
        OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset));
    }

    public bool Contains(T item)
    {
        return _internalList.Contains(item);
    }

    public void CopyTo(T[] array, int arrayIndex)
    {
        _internalList.CopyTo(array, arrayIndex);
    }

    public IEnumerator<T> GetEnumerator()
    {
        return _internalList.GetEnumerator();
    }

    public int IndexOf(T item)
    {
        return _internalList.IndexOf(item);
    }

    public void Insert(int index, T item)
    {
        _internalList.Insert(index, item);
        OnPropertyChanged(new PropertyChangedEventArgs(nameof(Count)));
        OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Add, item, index));
    }

    public bool Remove(T item)
    {
        var index = _internalList.IndexOf(item);
        var result = _internalList.Remove(item);
        if (result)
        {
            OnPropertyChanged(new PropertyChangedEventArgs(nameof(Count)));
            OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Remove, item, index));
        }

        return result;
    }

    public void RemoveAt(int index)
    {
        var item = _internalList[index];
        _internalList.RemoveAt(index);
        OnPropertyChanged(new PropertyChangedEventArgs(nameof(Count)));
        OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Remove, item, index));
    }

    IEnumerator IEnumerable.GetEnumerator()
    {
        return _internalList.GetEnumerator();
    }

    protected virtual void OnPropertyChanged(PropertyChangedEventArgs e)
    {
        PropertyChanged?.Invoke(this, e);
    }

    protected virtual void OnCollectionChanged(NotifyCollectionChangedEventArgs e)
    {
        CollectionChanged?.Invoke(this, e);
    }
}

var collection = new StateManagedCollection<string>();
collection.Add("Hello");
collection.Add("World");
foreach (var item in collection)
{
    Console.WriteLine(item);
}