C# Parse Link Header

c-sharp-parse-linkheader.cs

public class LinkHeader
{
    public string FirstLink { get; set; }
    public string PrevLink { get; set; }
    public string NextLink { get; set; }
    public string LastLink { get; set; }

    public static LinkHeader CreateInstance(HttpResponseMessage httpResponseMessage)
    {
      if (httpResponseMessage.Headers.Contains("Link"))
      {
        return CreateInstance(httpResponseMessage.Headers.GetValues("Link").FirstOrDefault());
      }

      return null;
    }
    
    public static LinkHeader CreateInstance(string linkHeaderStr)
    {
        LinkHeader linkHeader = null;

        if (!string.IsNullOrWhiteSpace(linkHeaderStr))
        {
            string[] linkStrings = linkHeaderStr.Split(',');

            if (linkStrings != null && linkStrings.Any())
            {
                linkHeader = new LinkHeader();

                foreach (string linkString in linkStrings)
                {
                    var relMatch = Regex.Match(linkString, "(?<=rel=\").+?(?=\")", RegexOptions.IgnoreCase);
                    var linkMatch = Regex.Match(linkString, "(?<=<).+?(?=>)", RegexOptions.IgnoreCase);

                    if (relMatch.Success && linkMatch.Success)
                    {
                        string rel = relMatch.Value.ToUpper();
                        string link = linkMatch.Value;

                        switch (rel)
                        {
                            case "FIRST":
                                linkHeader.FirstLink = link;
                                break;
                            case "PREV":
                                linkHeader.PrevLink = link;
                                break;
                            case "NEXT":
                                linkHeader.NextLink = link;
                                break;
                            case "LAST":
                                linkHeader.LastLink = link;
                                break;
                        }
                    }
                }
            }
        }

        return linkHeader;
    }
}