1.byte和str互转

b = b"example" 
s = "example" 
bytes(s, encoding = "utf8") 
str(b, encoding = "utf-8")

2.byte和int互转

b=b'\\x01\\x02'
num=int.from_bytes(b,'little')
b1=num.to_bytes(2,'little')

3.byte和float互转

import struct
s=b'@zQ\\x16'
def byteToFloat(b):
  return struct.unpack('!f',s)[0]

def floatToBytes(f):
  bs = struct.pack("f",f)
  return bytes((bs[3],bs[2],bs[1],bs[0]))
f1=byteToFloat(s)
floatToBytes(f1)

4.str和bytearray互转

str1='aaabb'
ba=bytearray(str1,encoding='utf-8')
str2=ba.decode('utf8')

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