コード例 #1
0
ファイル: PdfReaderExtensions.cs プロジェクト: sharp7/PDF-SDK
        /// <summary>
        /// Reads next <see cref="PdfObject"/> from PDF stream.
        /// </summary>
        /// <param name="reader">The <see cref="PdfReader"/> to use.</param>
        /// <returns>Read PdfObject.</returns>
        public static PdfObject ReadObject(this PdfReader reader)
        {
            if (reader == null)
            {
                throw new ArgumentNullException(nameof(reader));
            }

            reader.MoveToNonWhiteSpace();

            char firstChar = reader.Peek();

            switch (firstChar)
            {
            case '%':
                // Skip comment
                reader.SkipWhile(c => !Chars.IsEndOfLine(c));
                reader.SkipWhile(Chars.IsEndOfLine);
                // Then try read next object
                return(ReadObject(reader));

            case 't':
                reader.ReadToken(BooleanObject.TrueToken);
                return(new BooleanObject(true, true));

            case 'f':
                reader.ReadToken(BooleanObject.FalseToken);
                return(new BooleanObject(false, true));

            case 'n':
                reader.ReadToken(NullObject.NullToken);
                return(new NullObject());

            case '(':
                return(LiteralStringObject.FromReader(reader));

            case '<':
                if (reader.Peek(1) == '<')
                {
                    return(DictionaryObject.FromReader(reader));
                }
                else
                {
                    return(HexadecimalStringObject.FromReader(reader));
                }

            case '/':
                return(NameObject.FromReader(reader));

            case '[':
                return(ArrayObject.FromReader(reader));

            case '+':
            case '-':
                return(NumericObject.FromReader(reader));
            }
            if (char.IsDigit(firstChar))
            {
                int indRefLength = IsIndirectReference(reader);
                if (indRefLength >= 5)
                {
                    var indRefStr = reader.ReadString(indRefLength);
                    var objectId  = PdfObjectId.FromString(indRefStr.Substring(0, indRefLength - 2));

                    return(new IndirectReference(objectId));
                }

                return(NumericObject.FromReader(reader));
            }
            throw new NotImplementedException();
        }