I am given strings structured as such: "\x0C\x00Maximilianus\xf4\x01" and I would like to dynamically extract first two and last two bytes and convert them to decimals. The encoding for this should be UTF-8 little-endian unsigned.
"\x0C\x00" equals 12
"\xf4\x01" equals 500
I am not able to find any function that would be able to do that. Also replacing "\x" in the string doesn't work as I cannot manipulate with escape characters.
Any thoughts?
You can use struct to get numbers.
Using table Format Characters you can see you need "h" to convert 2-bytes integer.
You can eventually use "<h" to make sure it will use little-endian
import struct
# convert to bytes
data = "\x0C\x00Maximilianus\xf4\x01".encode('latin1')
# get short integer
number = struct.unpack('<h', data[:2])[0]
print('number:', number)
# skip number
data = data[2:]
# get string
#text = struct.unpack(f'{number}s', data[:number])[0] # use `number` to create `"12s"`
#print('text:', text.decode())
print('text:', data[:number].decode())
# skip string
data = data[number:]
# get short integer
number = struct.unpack('<h', data[:2])[0]
print('number:', number)
BTW: it looks similar to MessagePack so maybe there is special module for this but I don't know it.
data = "\x0C\x00Maximilianus\xf4\x01".encode('latin1') this was the line I was looking for. Then I can do int.from_bytes(data[:2],byteorder="little") to get the first part and int.from_bytes(data[-2:],byteorder="little") to get the last part.
So here is my final solution with the help from furas:
data = "\x0C\x00Maximilianus\xf4\x01".encode('latin1')
name_len = int.from_bytes(data[:2],byteorder="little")
ending = int.from_bytes(data[-2:],byteorder="little")
print(name_len) # --> 12
print(ending) # --> 500
struct.pack()to create it then usestruct.unpack()to convert it back.Maximilianushas 12 chars so"\x0C\x00"can be information how long is string and it can be some system to send data in networkprint(struct.unpack('hh', b"\x0C\x00\xf4\x01"))gives(12, 500)