<PackageReference Include="System.ServiceModel.Primitives" Version="8.0.0" />

System.Collections.Generic.SynchronizedReadOnlyCollection<T>

namespace System.Collections.Generic { public class SynchronizedReadOnlyCollection<T> : IList<T>, ICollection<T>, IEnumerable<T>, IEnumerable, IList, ICollection { public int Count { get; } protected IList<T> Items { get; } public T this[int index] { get; } T IList<T>.this[int index] { get; set; } object IList.this[int index] { get; set; } public SynchronizedReadOnlyCollection(); public SynchronizedReadOnlyCollection(object syncRoot); public SynchronizedReadOnlyCollection(object syncRoot, IEnumerable<T> list); public SynchronizedReadOnlyCollection(object syncRoot, params T[] list); public bool Contains(T value); public void CopyTo(T[] array, int index); public IEnumerator<T> GetEnumerator(); public int IndexOf(T value); } }