/// <summary>
/// Parse a string to long. String must not start with '0x'.
/// Long can accomodate only 16 meaningful hex-decimals.
/// </summary>
/// <param name="str">string of hexadecimal characters [0-9a-fA-F]</param>
/// <param name="value">result value</param>
/// <returns>false if contains non-hex characters, or if number of meaningful hexnumbers is over 24.</returns>
public static bool TryParseToULong(String str, out ulong value)
{
HexEnumerator stream = new HexEnumerator(str.GetEnumerator());
// Calculate hex character count
int count = 0;
// Calculate meaningful number characters
int meaningfulDigits = 0;
for (int i = 0; i < 999 && stream.MoveNext(); i++)
{
// Got non-hex value.
if (stream.Current < 0)
{
value = default(ulong); return(false);
}
// Start calculating after first non-zero.
if (meaningfulDigits > 0 || stream.Current != 0)
{
meaningfulDigits++;
}
// Total character count.
count++;
}
// Found non-zero value.
if (stream.Error)
{
value = default(ulong); return(false);
}
// Restart
stream.Reset();
// Too many characters
if (meaningfulDigits >= 17)
{
value = default(ulong); return(false);
}
value = 0UL;
while (count > 16 && stream.MoveNext())
{
// long can fit 64bit value, any non-zero over 64bits cannot be parsed.
if (stream.Current != 0)
{
value = default(ulong); return(false);
}
count--;
}
while (count > 0 && stream.MoveNext())
{
ulong hex = (ulong)stream.Current;
value = value << 4 | hex;
count--;
}
return(true);
}
/// <summary>
/// Parse a string to uint. String must not start with '0x'.
/// UInt can accomodate only 8 meaningful hex-decimals.
/// </summary>
/// <param name="str">string of hexadecimal characters [0-9a-fA-F]</param>
/// <param name="startIndex">character start index</param>
/// <returns>value</returns>
/// <exception cref="System.FormatException"></exception>
public static uint ToUInt(String str, int startIndex = 0)
{
CharEnumerator enumr = str.GetEnumerator();
for (int i = 0; i < startIndex; i++)
{
if (!enumr.MoveNext())
{
throw new FormatException("End of stream before startIndex.");
}
}
HexEnumerator stream = new HexEnumerator(enumr);
// Calculate hex character count
int count = 0;
// Calculate meaningful number characters
int meaningfulDigits = 0;
for (int i = 0; i < 999 && stream.MoveNext(); i++)
{
// Got non-hex value.
if (stream.Current < 0)
{
throw new System.FormatException("Unexpected character in hex stream.");
}
// Start calculating after first non-zero.
if (meaningfulDigits > 0 || stream.Current != 0)
{
meaningfulDigits++;
}
// Total character count.
count++;
}
// Found non-zero value.
if (stream.Error)
{
if (stream.Current < 0)
{
throw new System.FormatException("Unexpected character in hex stream.");
}
}
// Restart
stream.Reset();
for (int i = 0; i < startIndex; i++)
{
enumr.MoveNext();
}
// Too many characters
if (meaningfulDigits >= 9)
{
throw new System.FormatException("Hex value too large to fit into decimal.");
}
uint value = 0U;
while (count > 8 && stream.MoveNext())
{
// long can fit 64bit value, any non-zero over 64bits cannot be parsed.
if (stream.Current != 0)
{
throw new System.FormatException("Hex value too large to fit into decimal.");
}
count--;
}
while (count > 0 && stream.MoveNext())
{
uint hex = (uint)stream.Current;
value = value << 4 | hex;
count--;
}
return(value);
}
/// <summary>
/// Try to parse a string to decimal number.
/// String must not start with '0x'.
/// Decimal can accomodate only 24 meaningful hexnumbers.
/// Although, the string can precede any number of zeroes, e.g. "0000000000000000000000000000000000000000000000000000000000000123123abff".
/// </summary>
/// <param name="str">string of hexadecimal characters [0-9a-fA-F]</param>
/// <param name="value">result value</param>
/// <returns>false if contains non-hex characters, or if number of meaningful hexnumbers is over 24.</returns>
public static bool TryParseToDecimal(String str, out decimal value)
{
HexEnumerator stream = new HexEnumerator(str.GetEnumerator());
// Calculate hex character count
int count = 0;
// Calculate meaningful number characters
int meaningfulDigits = 0;
for (int i = 0; i < 999 && stream.MoveNext(); i++)
{
// Got non-hex value.
if (stream.Current < 0)
{
value = 0; return(false);
}
// Start calculating after first non-zero.
if (meaningfulDigits > 0 || stream.Current != 0)
{
meaningfulDigits++;
}
// Total character count.
count++;
}
// Found non-zero value.
if (stream.Error)
{
value = 0; return(false);
}
// Restart
stream.Reset();
// Too many characters
if (meaningfulDigits >= 25)
{
value = 0; return(false);
}
int lo = 0, mid = 0, hi = 0;
while (count > 24 && stream.MoveNext())
{
// decimal can fit 96bit value, any non-zero over 96bits cannot be parsed.
if (stream.Current != 0)
{
value = 0; return(false);
}
count--;
}
while (count > 16 && stream.MoveNext())
{
hi = (hi << 4) | stream.Current;
count--;
}
while (count > 8 && stream.MoveNext())
{
mid = (mid << 4) | stream.Current;
count--;
}
while (count > 0 && stream.MoveNext())
{
lo = (lo << 4) | stream.Current;
count--;
}
value = new decimal(lo, mid, hi, false, 0);
return(!stream.Error);
}
