1 反转字符串¶
st="python"
#方法1
''.join(reversed(st))
#方法2
st[::-1]
2 字符串切片操作¶
字符串切片操作——查找替换3或5的倍数
In [1]:[str("java"[i%3*4:]+"python"[i%5*6:] or i) for i in range(1,15)]
OUT[1]:['1',
'2',
'java',
'4',
'python',
'java',
'7',
'8',
'java',
'python',
'11',
'java',
'13',
'14']
3 join串联字符串¶
In [4]: mystr = ['1',
...: '2',
...: 'java',
...: '4',
...: 'python',
...: 'java',
...: '7',
...: '8',
...: 'java',
...: 'python',
...: '11',
...: 'java',
...: '13',
...: '14']
In [5]: ','.join(mystr) #用逗号连接字符串
Out[5]: '1,2,java,4,python,java,7,8,java,python,11,java,13,14'
4 字符串的字节长度¶
def str_byte_len(mystr):
return (len(mystr.encode('utf-8')))
str_byte_len('i love python') # 13(个字节)
str_byte_len('字符') # 6(个字节)