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

System.Net.Http.Headers.HttpHeaderValueCollection<T>

namespace System.Net.Http.Headers { public sealed class HttpHeaderValueCollection<T> : ICollection<T>, IEnumerable<T>, IEnumerable where T : class { public int Count { get; } public bool IsReadOnly { get; } public void Add(T item); public void Clear(); public bool Contains(T item); public void CopyTo(T[] array, int arrayIndex); public IEnumerator<T> GetEnumerator(); public void ParseAdd(string input); public bool Remove(T item); public bool TryParseAdd(string input); } }