public static string ToHexString(this byte[] data) {
var lookup = new[] { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };
int i = -1, p = -1, l = data.Length;
var c = new char[l-- * 2];
while (i < l) {
var d = data[++i];
c[++p] = lookup[d >> 4];
c[++p] = lookup[d & 0xF];
}
return new string(c, 0, c.Length);
}
}