MvcApi.Formatting.MediaTypeFormatter.SelectCharacterEncoding C# (CSharp) Метод

        public Encoding SelectCharacterEncoding(HttpRequestMessage contentHeaders)
        {
            Encoding encoding = null;
            if (contentHeaders != null && contentHeaders.ContentType != null)
            {
                // Find encoding based on content type charset parameter
                string charset = contentHeaders.ContentType.CharSet;
                if (!String.IsNullOrWhiteSpace(charset))
                {
                    encoding =
                        SupportedEncodings.FirstOrDefault(
                            enc => charset.Equals(enc.WebName, StringComparison.OrdinalIgnoreCase));
                }
            }

            if (encoding == null)
            {
                // We didn't find a character encoding match based on the content headers.
                // Instead we try getting the default character encoding.
                encoding = SupportedEncodings.FirstOrDefault();
            }

            if (encoding == null)
            {
                // No supported encoding was found so there is no way for us to start reading or writing.
                throw new InvalidOperationException(string.Format(SRResources.MediaTypeFormatterNoEncoding, GetType().Name));
            }

            return encoding;
        }

        /// <summary>
        /// Determine the best character encoding for writing the response. First we look
        /// for accept-charset headers and if not found then we try to match
        /// any charset encoding in the request (in case of PUT, POST, etc.)
        /// If no encoding is found then we use the default for the formatter.
        /// </summary>
        /// <returns>The <see cref="Encoding"/> determined to be the best match.</returns>
        protected virtual Encoding SelectResponseCharacterEncoding(HttpRequestMessage request, MediaTypeFormatter formatter)
        {
            if (request == null)
            {
                throw Error.ArgumentNull("request");
            }
            if (formatter == null)
            {
                throw Error.ArgumentNull("formatter");
            }

            // If there are any SupportedEncodings then we pick an encoding
            if (formatter.SupportedEncodings.Count > 0)
            {
                // Sort Accept-Charset header values
                //IEnumerable<StringWithQualityHeaderValue> sortedAcceptCharsetValues = SortStringWithQualityHeaderValuesByQFactor(request.Headers.AcceptCharset);
                // TODO: Fix instead of using Formatter.SelectCharacterEncoding();
                IEnumerable<StringWithQualityHeaderValue> sortedAcceptCharsetValues = Enumerable.Empty<StringWithQualityHeaderValue>();

                // Check for match based on accept-charset headers
                foreach (StringWithQualityHeaderValue acceptCharset in sortedAcceptCharsetValues)
                {
                    foreach (Encoding encoding in formatter.SupportedEncodings)
                    {
                        if (encoding != null && acceptCharset.Quality != FormattingUtilities.NoMatch &&
                            (acceptCharset.Value.Equals(encoding.WebName, StringComparison.OrdinalIgnoreCase) ||
                            acceptCharset.Value.Equals("*", StringComparison.OrdinalIgnoreCase)))
                        {
                            return encoding;
                        }
                    }
                }

                // Check for match based on any request entity body
                return formatter.SelectCharacterEncoding(request);
            }

            return null;
        }