字符串格式化
>>> '%s plus %s equals %s' % (1,1,2)
'1 plus 1 equals 2'
字段的宽度和精度
*字段宽度是转换后的值所保留的最小字符个数，精度（对于数字）是包含的小数位数，或者（对于字符）转换后的值所能包含的最大字符数
>>> from math import pi
>>> '%10f' % pi
' 3.141593'
>>> from math import pi
>>> '%10f' % pi #字段宽10
' 3.141593'
>>> '%10.2f' % pi #字段宽10，精度2
' 3.14'
>>> '%.2f' % pi #精度2
'3.14'
>>> '%.5s' % 'my name is ningsi'
'my na'
>>> '%.*s' % (5,'my name is ningsi')
'my na'
符号、对齐和0填充
>>> '%010.2f' % pi #用0填充
'0000003.14'
>>> '%-10.2f' % pi #左对齐
'3.14 '
>>> print ('% 5d' % 10)+'\n'+('%5d' % -10)
10
-10
>>> print ('%+5d' % 10)+'\n'+('%+5d' % -10)
+10
-10
字符串的方法
find 查找子字符串
>>> n='ning si de shu de'>>> n.find('de')8
>>> n.find('dee')-1
>>> n.find('de',9,16) #范围包含第一个索引不包含第二个-1
join 是split方法的逆方法
>>> s=['1','2','3','4']
>>> q.join(s)
'1+2+3+4'
>>> p='','usr','bin','env'
>>> '/'.join(p)
'/usr/bin/env'>>> print 'c:'+'\\'.join(p)
c:\usr\bin\env
lower 返回字符串的小写字母版
>>> 'my name is ningsideshu'.lower()
'my name is ningsideshu'
>>> if 'name' in ['my','name','is']:print 'found it!'
>>> if 'my' in ['my','name','is']:print 'found it!'
found it!
replace 替换
>>> 'this is a pen'.replace('pen','apple')'this is a apple'
split 将字符串分割成序列
>>> '1+2+3+4+5'.split('+')
['1', '2', '3', '4', '5']
>>> '/usr/bin/env'.split('/')
['', 'usr', 'bin', 'env']
>>> 'using the default'.split() #默认所有空格作为分隔符（空格、换行等）
['using', 'the', 'default']
strip 返回去除两侧空格（或指定字符）的字符串 (另外：lstrip,rstrip)
>>> ' my name is nsds '.strip()'my name is nsds'>>> ' *my name is nsds * '.strip(' *')'my name is nsds'
translate 替换，与replace不同的是，可以替换单个字符（字符串中的某些部分）
>>> from string import maketrans
>>> n=maketrans('ns','mf')
>>> 'my name is ningsideshu'.translate(n)
'my mame if mimgfidefhu'
>>> 'my name is ningsideshu'.translate(n,'m') #第二个参数指定需要删除的字符
'y mame if mimgfidefhu'
模版字符串
>>> from string import template
>>> s=template('$x. name $x!')
>>> s.substitute(x='hello')
'hello. name hello!'
>>> s=template("it't ${x}tastic!")
>>> s.substitute(x='slurm')
"it't slurmtastic!"
>>> s=template("it't ${x}tastic${y}!")
>>> s.substitute(x='slurm',y='a')
"it't slurmtastica!"
>>> s=template('a $thing must never $action.')
>>> d={}
>>> d['thing']='gentleman'
>>> d['action']='show his socks'
>>> s.substitute(d)
'a gentleman must never show his socks.'
以上就是python中字符串的几个方法的详细说明的详细内容。