1，首字母大写
>>> s = ‘ghostwu‘ >>> s.capitalize() ‘Ghostwu‘
2，replace，替换
>>> s = ‘my name is ghostwu, age is 20‘ >>> s ‘my name is ghostwu, age is 20‘ >>> s.replace( ‘20‘, ‘30‘ ) ‘my name is ghostwu, age is 30‘ >>> s ‘my name is ghostwu, age is 20‘ >>>
查帮助
>>> help( str.replace )
如果是面向过程的函数用法，直接help( 函数名 )，如help( abs )
用法说明：
replace(...)
S.replace(old, new[, count]) -> string
Return a copy of string S with all occurrences of substring
old replaced by new. If the optional argument count is
given, only the first count occurrences are replaced.
接受3个参数，第一个需要替换的字符，第二个用什么字符去替换，第三个替换的次数，如果不传，默认全部替换
1 >>> str = ‘121212‘ 2 >>> str.replace( ‘1‘, ‘g‘ ) 3 ‘g2g2g2‘ 4 >>> str.replace( ‘1‘, ‘g‘, 1 ) 5 ‘g21212‘ 6 >>> str.replace( ‘1‘, ‘g‘, 2 ) 7 ‘g2g212‘ 8 >>> str.replace( ‘1‘, ‘g‘, 3 ) 9 ‘g2g2g2‘
3，split：切割
1 >>> ip=‘127.0.0.1‘ 2 >>> ip 3 ‘127.0.0.1‘ 4 >>> ip.split( ‘.‘ ) 5 [‘127‘, ‘0‘, ‘0‘, ‘1‘] 6 >>> ip.split( ‘.‘, 1 ) 7 [‘127‘, ‘0.0.1‘] 8 >>> ip.split( ‘.‘, 2 ) 9 [‘127‘, ‘0‘, ‘0.1‘] 10 >>> ip.split( ‘.‘, 3 ) 11 [‘127‘, ‘0‘, ‘0‘, ‘1‘] 12 >>>
4，用string模块，用法如下：
1 >>> import string 2 >>> help( string.capitalize ) 3 4 >>> s = ‘ghostwu‘ 5 >>> string.capitalize( s ) 6 ‘Ghostwu‘
1 >>> import string 2 >>> s = ‘my name is ghostwu, age is 20‘ 3 >>> string.replace( s, ‘20‘, ‘30‘ ) 4 ‘my name is ghostwu, age is 30‘ 5 >>> ip 6 ‘127.0.0.1‘ 7 >>> string.split( ip, ‘.‘ ) 8 [‘127‘, ‘0‘, ‘0‘, ‘1‘] 9 >>> string.split( ip, ‘.‘, 1 ) 10 [‘127‘, ‘0.0.1‘] 11 >>>
5，filter：过滤， 利用这个函数，筛选出一个序列的偶数
1 >>> def isEven( n ): 2 ... if n % 2 == 0: 3 ... return True 4 ... 5 >>> isEven( 10 ) 6 True 7 >>> isEven( 3 ) 8 >>> range( 10 ) 9 [0, 1, 2, 3, 4, 5, 6, 7, 8, 9] 10 >>> l = range( 10 ) 11 >>> filter( isEven, l ) 12 [0, 2, 4, 6, 8] 13 >>>
