Get Mime Type using C#

 public static string GetMimeType(string fileName)
    {
        string mimeType = "application/unknown";
        string ext = System.IO.Path.GetExtension(fileName).ToLower();
        RegistryKey regKey = Registry.ClassesRoot.OpenSubKey(ext);
        if (regKey != null && regKey.GetValue("Content Type") != null)
            mimeType = regKey.GetValue("Content Type").ToString();
        return mimeType;
    }