/// <summary> /// Check if a target directive exists among the set of given cache control directives. /// </summary> /// <param name="cacheControlDirectives"> /// The <see cref="StringValues"/> containing the set of cache control directives. /// </param> /// <param name="targetDirectives"> /// The target cache control directives to look for. /// </param> /// <returns> /// <code>true</code> if <paramref name="targetDirectives"/> is contained in <paramref name="cacheControlDirectives"/>; /// otherwise, <code>false</code>. /// </returns> public static bool ContainsCacheDirective(StringValues cacheControlDirectives, string targetDirectives) { if (StringValues.IsNullOrEmpty(cacheControlDirectives) || string.IsNullOrEmpty(targetDirectives)) { return(false); } for (var i = 0; i < cacheControlDirectives.Count; i++) { // Trim leading white space var current = HttpRuleParser.GetWhitespaceLength(cacheControlDirectives[i], 0); while (current < cacheControlDirectives[i].Length) { var initial = current; var tokenLength = HttpRuleParser.GetTokenLength(cacheControlDirectives[i], current); if (tokenLength == targetDirectives.Length && string.Compare(cacheControlDirectives[i], current, targetDirectives, 0, tokenLength, StringComparison.OrdinalIgnoreCase) == 0) { // Token matches target value return(true); } current = AdvanceCacheDirectiveIndex(current + tokenLength, cacheControlDirectives[i]); // Ensure index was advanced if (current <= initial) { Debug.Assert(false, $"Index '{nameof(current)}' not advanced, this is a bug."); return(false); } } } return(false); }
public static bool TryParseDate(StringSegment input, out DateTimeOffset result) { return(HttpRuleParser.TryStringToDate(input, out result)); }