/// <summary>
/// Creates an accessor depending on the format.
/// </summary>
/// <param name="start">the zero-based index of the first byte of the accessor</param>
/// <param name="length">the length of the accessor</param>
/// <param name="format">the format of the accessor</param>
/// <param name="encoding">the encoding of the accessed records</param>
/// <returns>a new accessor with the correct parameters</returns>
protected object GetAccessor(int start, int length, string format, Encoding encoding)
{
object result;
switch (format)
{
case StringFormat:
case SubstringFormat:
result = new StringAccessor {
Encoding = encoding, Start = start, Length = length
};
break;
case ZonedFormat:
result = new ZonedAccessor {
Encoding = encoding, Length = length, Start = start
};
break;
case PackedFormat:
result = new PackedAccessor {
Encoding = encoding, Length = length, Start = start
};
break;
case SignedBinaryFormat:
result = new BinaryAccessor {
Encoding = encoding, Length = length, Start = start, Signed = true
};
break;
case BinaryFormat:
result = new BinaryAccessor {
Encoding = encoding, Length = length, Start = start, Signed = false
};
break;
default:
throw new ParsingException("Unknown format: " + format);
}
return(result);
}
/// <summary>
/// Creates an accessor depending on the format.
/// </summary>
/// <param name="start">the zero-based index of the first byte of the accessor</param>
/// <param name="length">the length of the accessor</param>
/// <param name="format">the format of the accessor</param>
/// <param name="encoding">the encoding of the accessed records</param>
/// <returns>a new accessor with the correct parameters</returns>
protected object GetAccessor(int start, int length, string format, Encoding encoding)
{
object result;
switch (format)
{
case StringFormat:
case SubstringFormat:
result = new StringAccessor { Encoding = encoding, Start = start, Length = length };
break;
case ZonedFormat:
result = new ZonedAccessor { Encoding = encoding, Length = length, Start = start };
break;
case PackedFormat:
result = new PackedAccessor { Encoding = encoding, Length = length, Start = start };
break;
case SignedBinaryFormat:
result = new BinaryAccessor { Encoding = encoding, Length = length, Start = start, Signed = true };
break;
case BinaryFormat:
result = new BinaryAccessor { Encoding = encoding, Length = length, Start = start, Signed = false };
break;
default:
throw new ParsingException("Unknown format: " + format);
}
return result;
}
/// <summary>
/// Parses an accessor.
/// </summary>
/// <param name="lexer">the lexer to read the tokens from</param>
/// <param name="defaultFormat">the default format</param>
/// <param name="format">the format of the parsed accessor</param>
/// <returns>an <see cref="IAccessor{T}"/></returns>
private object ParseAccessor(Lexer lexer, string defaultFormat, out string format)
{
var elements = new List<string>();
format = null;
do
{
elements.Add(lexer.Current);
} while (lexer.MoveNext() && lexer.Current != ClosingPar &&
!LogicalOperators.Contains(lexer.Current) && !ComparisonOperators.Contains(lexer.Current));
if (elements.Count == 1)
{
// decimal constant
return new ConstantAccessor<decimal> { Constant = decimal.Parse(elements[0]) };
}
if (elements.Count == 2 && elements[0] == "C")
{
// string constant
var constant = elements[1].Substring(1, elements[1].Length - 2);
return new ConstantAccessor<string> { Constant = constant };
}
if (elements.Count == 2 && elements[0] == "X")
{
// HexaDecimal constant
var constant = elements[1].Substring(1, elements[1].Length - 2);
BinaryAccessor accessor = new BinaryAccessor ();
int value = Convert.ToInt32(constant, 16);
byte[] bytes = Enumerable.Range(0, constant.Length).Where(x => x % 2 == 0).Select(x => Convert.ToByte(constant.Substring(x, 2), 16)).ToArray();
accessor.SetBytes(bytes, bytes, 0);
decimal constant1 = Convert.ToInt32(constant, 16);
return new ConstantAccessor<decimal> { Constant = constant1 };
}
// field accesor
var start = int.Parse(elements[0]) - 1;
var length = int.Parse(elements[1]);
format = elements.Count == 3 ? elements[2] : defaultFormat;
return GetAccessor(start, length, format, Encoding);
}
/// <summary>
/// Creates an accessor depending on the format.
/// </summary>
/// <param name="start">the zero-based index of the first byte of the accessor</param>
/// <param name="length">the length of the accessor</param>
/// <param name="format">the format of the accessor</param>
/// <param name="encoding">the encoding of the accessed records</param>
/// <returns>a new accessor with the correct parameters</returns>
protected object GetAccessor(int start, int length, string format, Encoding encoding)
{
object result;
switch (format)
{
case StringFormat:
case SubstringFormat:
result = new StringAccessor {
Encoding = encoding, Start = start, Length = length
};
break;
case ZonedFormat:
result = new ZonedAccessor {
Encoding = encoding, Length = length, Start = start
};
break;
case PackedFormat:
result = new PackedAccessor {
Encoding = encoding, Length = length, Start = start
};
break;
case SignedBinaryFormat:
result = new BinaryAccessor {
Encoding = encoding, Length = length, Start = start, Signed = true
};
break;
case BinaryFormat:
result = new BinaryAccessor {
Encoding = encoding, Length = length, Start = start, Signed = false
};
break;
default:
if (format != null && format.StartsWith(AsciiDecimalFormat))
{
int precision = 0;
if (format.Length > 2)
{
precision = int.Parse(format.Substring(2));
result = new AsciiAcessor {
Encoding = encoding, Length = length, Start = start, Precision = precision
};
}
else
{
throw new ParsingException("Unknown format: " + format);
}
break;
}
else
{
throw new ParsingException("Unknown format: " + format);
}
}
return(result);
}
