15 个最佳开源设计工具

总结下最近学习lerning python这本书的字符串部分的一些收获吧。
一、原始字符串
在普通字符串前加‘r'即成为原始字符串，特点是抑制转义，即在原始字符串中’\n‘这种转义字符串没有特殊含义了。
二、索引和分片
s = 'abcdefg'
s[1:5:2] = 'ace'
s[5:1:-1] = 'fedc'
s[::-1] = 'gfedcba'
三、字符串转换工具
int('42') = 42
str(42) = '42'
ord('s') = 115
chr(115) = 's'
四、修改字符串
s = 'spam'
s[0] = 'a' error!!!不能原处修改
s = s + 'hello'
s = s[4:] + ' world' = 'hello world'

五、字符串方法
s = 'hello world'
(1) replace
s.replace( 'o', 'x' ) = 'hellx, wxrld'
(2) join

l = list( s ) = ['h', 'e', 'l', 'l', 'o', ' ', 'w', 'o', 'r', 'l', 'd']
' '.join( l ) = 'hello world'
','.join( ['hello', 'world'] ) = 'hello,world'
'spam'.join( ['hello', 'world'] ) = 'hellospamworld'
(3) split
line = 'aaa bbb ccc'
line.split() = ['aaa', 'bbb', 'ccc'] //如果不加任何参数默认用空格来分割
line = 'bob,hacker,40'
line.split( ',' ) = ['bob', 'hacker', '40']
(4) rstrip, lstrip //分别是去除字符串右端和左端的空白

line = 'the knights who say hi!\n'
line.rstrip() = 'the knights who sya hi!' //去除行末的空白

(5) endswith, startswith //rt
(6) find
'hello, world'.find( 'o' ) = 4

本文出自 “sdu_IS” 博客，请务必保留此出处http://hychuanshuo.blog.51cto.com/2724628/1239093