Python中bytes和str的区别与联系详解

a = b'hello world'
print(isinstance(a, bytes))
print(list(a))
print(a)
"""
True
[104, 101, 108, 108, 111, 32, 119, 111, 114, 108, 100]
b'hello world'
"""

a = 'hello world'
print(isinstance(a, str))
print(list(a))
print(a)
"""
True
['h', 'e', 'l', 'l', 'o', ' ', 'w', 'o', 'r', 'l', 'd']
hello world
"""

x = b'python'
y = b'java'
z = 'c++'
w = 'c'

print(x + y)
# b'pythonjava'
print(z + w)
# c++c
print(x + z)
# TypeError: can't concat str to bytes

print('python' == b'python')
# False

x = b'python'
y = x.decode(encoding='utf-8')
z = y.encode(encoding='utf-8')
print(y)
print(z)
"""
python
b'python'
"""

x = b'python'

# 错误示例
with open('data.bin', mode='w') as fp:
    fp.write(x)
# TypeError: write() argument must be str, not bytes

# 正确示例
with open('data.bin', mode='wb') as fp:
    fp.write(x)

# 读取二进制文件方式1
with open('data.bin', mode='rb') as fp:
    content = fp.read()
    print(content)
# python

# 读取二进制文件方式2
with open('data.bin', mode='r', encoding='utf-8') as fp:
    content = fp.read()
    print(content, type(content))
# python <class 'str'>

x = '世界你好'

with open('data.txt', mode='w', encoding='utf-8') as fp:
    fp.write(x)

with open('data.txt', mode='r', encoding='utf-8') as fp:
    content = fp.read()
    print(content)
# 世界你好

# 错误示例，编码方式不对
with open('data.txt', mode='r', encoding='gbk') as fp:
    content = fp.read()
    print(content)
# 涓栫晫浣犲ソ