16進文字列とByte間の相互回転
2871 ワード
public static class ByteHexHelper
{
private static char[] _buffedChars = null;
private static byte[] _buffedBytes = null;
static ByteHexHelper()
{
_buffedChars = new char[(byte.MaxValue - byte.MinValue + 1) * 2];
int idx = 0;
byte b = byte.MinValue;
while (true)
{
string hexs = b.ToString("X2");
_buffedChars[idx++] = hexs[0];
_buffedChars[idx++] = hexs[1];
if (b == byte.MaxValue) break;
++b;
}
_buffedBytes = new byte[0x67];
idx = _buffedBytes.Length;
while (--idx >= 0)
{
if ((0x30 <= idx) && (idx <= 0x39))
{
_buffedBytes[idx] = (byte)(idx - 0x30);
}
else
{
if ((0x61 <= idx) && (idx <= 0x66))
{
_buffedBytes[idx] = (byte)((idx - 0x61) + 10);
continue;
}
if ((0x41 <= idx) && (idx <= 70))
{
_buffedBytes[idx] = (byte)((idx - 0x41) + 10);
}
}
}
}
/// <summary>
/// 16
/// </summary>
/// <param name="bytes"></param>
/// <returns></returns>
public static string ByteToHex(byte[] bytes)
{
if (bytes == null)
{
return null;
}
char[] result = new char[bytes.Length * 2];
for (int i = 0; i < bytes.Length; ++i)
{
int startIndex = (bytes[i] - byte.MinValue) * 2;
result[i * 2] = _buffedChars[startIndex];
result[i * 2 + 1] = _buffedChars[startIndex + 1];
}
return new string(result);
}
/// <summary>
/// 16
/// </summary>
/// <param name="str"></param>
/// <returns></returns>
public static byte[] HexToByte(string str)
{
if (str == null || (str.Length & 1) == 1)
{
return null;
}
byte[] result = new byte[str.Length / 2];
int charIndex = 0;
int byteIndex = 0;
int length = result.Length;
while (--length >= 0)
{
int first = 0;
int second = 0;
try
{
first = _buffedBytes[str[charIndex++]];
second = _buffedBytes[str[charIndex++]];
}
catch
{
return null;
}
result[byteIndex++] = (byte)((first << 4) + second);
}
return result;
}
}