十六进制和字符串上的Python XOR(奇偶校验功能)

时间:2014-04-28 15:47:10

标签: c# python hex xor parity

我遇到了Hex值和python的问题。我正在尝试编写一个执行字节XOR并返回Hex值的函数。

基本上我试图将这个C#代码转换为Python:

private byte[] AddParity(string _in)
{
byte parity = 0x7f;
List<byte> _out = new List<byte>();
ASCIIEncoding asc = new ASCIIEncoding();

byte[] bytes = asc.GetBytes(_in + '\r');
foreach (byte bt in bytes)
    {
    parity ^= bt;
    _out.Add(bt);
    }
_out.Add(parity);
return _out.ToArray();
}

有人能指出我正确的方向吗?

1 个答案:

答案 0 :(得分:1)

parity = 0x7f
parities = [int(item,16) ^ parity for item in "4e 7f 2b".split()]
#or maybe
parities = [ord(item) ^ parity for item in "somestring"]

我猜你用它作为某种校验和

parity = 0x7f
bits = []
for bit in "somestring":
    parity ^= ord(bit)
    parity &= 0xFF #ensure width
    bits.append(bit)
bits.append(parity)

你可以做更多的pythonically来做校验和


这是您想要的答案

bytestring = "vTest\r"
bits = chr(0x7f) + bytestring
checksum = reduce(lambda x,y:chr((ord(x)^ord(y))&0xff),bits)
message = bytestring+checksum
print map(lambda x:hex(ord(x)),message)
#Result:['0x76', '0x54', '0x65', '0x73', '0x74', '0xd', '0x32']
# ser.write(message)

如果要查看十六进制值

print map(hex,parities)

或查看二进制文件

print map(bin,parities)