<PackageReference Include="NETStandard.Library" Version="2.0.0-preview2-25401-01" />

System.Net.Http.Headers.HttpContentHeaders

public sealed class HttpContentHeaders : HttpHeaders
public ICollection<string> Allow { get; }

public ContentDispositionHeaderValue ContentDisposition { get; set; }

public ICollection<string> ContentEncoding { get; }

public ICollection<string> ContentLanguage { get; }

public long? ContentLength { get; set; }

public Uri ContentLocation { get; set; }

public byte[] ContentMD5 { get; set; }

public ContentRangeHeaderValue ContentRange { get; set; }

public MediaTypeHeaderValue ContentType { get; set; }

public DateTimeOffset? Expires { get; set; }

public DateTimeOffset? LastModified { get; set; }