System.Net.Http.Headers.Lexer.TryGetDoubleValue C# (CSharp) Method

		public bool TryGetDoubleValue (Token token, out double value)
		{
			string s = GetStringValue (token);
			return double.TryParse (s, NumberStyles.AllowDecimalPoint, CultureInfo.InvariantCulture, out value);
		}

        static bool TryParseElement(Lexer lexer, out StringWithQualityHeaderValue parsedValue, out Token t)
        {
            parsedValue = null;
            t           = lexer.Scan();
            if (t != Token.Type.Token)
            {
                return(false);
            }

            var value = new StringWithQualityHeaderValue();

            value.Value = lexer.GetStringValue(t);

            t = lexer.Scan();
            if (t == Token.Type.SeparatorSemicolon)
            {
                t = lexer.Scan();
                if (t != Token.Type.Token)
                {
                    return(false);
                }

                var s = lexer.GetStringValue(t);
                if (s != "q" && s != "Q")
                {
                    return(false);
                }

                t = lexer.Scan();
                if (t != Token.Type.SeparatorEqual)
                {
                    return(false);
                }

                t = lexer.Scan();

                double d;
                if (!lexer.TryGetDoubleValue(t, out d))
                {
                    return(false);
                }

                if (d > 1)
                {
                    return(false);
                }

                value.Quality = d;

                t = lexer.Scan();
            }

            parsedValue = value;
            return(true);
        }