python-day7-字符串类型的内置方法

# name='egon' #name=str('egon')
# print(type(name))


#优先掌握
#    移除空白strip
# msg=' hello '
# print(msg)
# print(msg.strip())

# msg='***hello*********'
# msg=msg.strip('*')
# print(msg)

# print(msg.lstrip('*')) #lstrip是已移除首部分的*
# print(msg.rstrip('*')) #rstrip是已移除尾部分的*

#用处
# while True:
# name=input('user: ').strip()
# password=input('password: ').strip()
#
# if name == 'egon' and password == '123':
# print('login successfull')



#     切分split
# info='root:x:0:0::/root:/bin/bash'
# print(info[0]+info[1]+info[2]+info[3])

# user_l=info.split(':')
# print(user_l[0])

# msg='hello world egon say hahah'
# print(msg.split()) #默认以空格作为分隔符

# cmd='download|xhp.mov|3000'
# cmd_l=cmd.split('|')
# print(cmd_l[1])
# print(cmd_l[0])

# print(cmd.split('|',1))

#name='a|b|c'
#print(name.rsplit('|',1)) #从右开始切分


# 用处
# while True:
# cmd=input('>>: ').strip()
# if len(cmd) == 0:continue
# cmd_l=cmd.split()
# print('命令是:%s 命令的参数是:%s' %(cmd_l[0],cmd_l[1]))




#     长度len

# print(len('hell 123'))


#     索引


#     切片:切出子字符串
# msg='hello world'
# print(msg[1:3]) #1 2
# print(msg[1:4]) #1 2 3



# 掌握部分
# oldboy_age=84
# while True:
# age=input('>>: ').strip()
# if len(age) == 0:continue
# if age.isdigit():
# age=int(age)
# else:
# print('must be int')





#startswith,endswith
# name='alex_SB'
# print(name.endswith('SB'))
# print(name.startswith('alex'))


#replace
# name='alex say :i have one tesla,my name is alex'
# print(name.replace('alex','SB',1))

# print('my name is %s my age is %s my sex is %s' %('egon',18,'male'))

#format的三种玩法
# print('my name is {} my age is {} my sex is {}'.format('egon',18,'male'))
# print('my name is {0} my age is {1} my sex is {0}:{2}'.format('egon',18,'male'))
# print('my name is {name} my age is {age} my sex is {sex}'.format(
# sex='male',
# age=18,
# name='egon'))


# #find,rfind,index,rindex,count
# name='geeon say hello'
# print(name.find('S',1,3)) #顾头不顾尾,找不到则返回-1不会报错,找到了则显示索引
# print(name.index('e')) #同上,但是找不到会报错,如果不指定范围则查找所有
# print(name.count('e',1,5)) #顾头不顾尾,如果不指定范围则查找所有

#join
# info='root:x:0:0::/root:/bin/bash'
# print(info.split(':'))

# l=['root', 'x', '0', '0', '', '/root', '/bin/bash']
# print(':'.join(l)) #把 : 加入到 l 列表

#tag=' '
#print(tag.join(['egon','say','hello','world'])) #可迭代对象必须都是字符串



# lower,upper
# name='eGon'
# print(name.lower())
# print(name.upper())






#了解部分
#expandtabs
# name='egon\thello'
# print(name)
# print(name.expandtabs(1))


#center,ljust,rjust,zfill
# name='egon'
# # print(name.center(30,'-'))
# print(name.ljust(30,'*'))
# print(name.rjust(30,'*'))
# print(name.zfill(50)) #用0填充


#captalize,swapcase,title
# name='eGon'
# print(name.capitalize()) #首字母大写,其余部分小写
# print(name.swapcase()) #大小写翻转
# msg='egon say hi'
# print(msg.title()) #每个单词的首字母大写




# #is数字系列
#在python3中
# num0='4'
# num1=b'4' #bytes
# num2=u'4' #unicode,python3中无需加u就是unicode
# num3='四' #中文数字
# num4='Ⅳ' #罗马数字

#isdigt:str,bytes,unicode
# print(num0.isdigit()) #True
# print(num1.isdigit()) #True
# print(num2.isdigit()) #True
# print(num3.isdigit()) #False
# print(num4.isdigit()) #False

#isdecimal:str,unicode
# num0='4'
# num1=b'4' #bytes
# num2=u'4' #unicode,python3中无需加u就是unicode
# num3='四' #中文数字
# num4='Ⅳ' #罗马数字
# print(num0.isdecimal()) #True
# # print(num1.)
# print(num2.isdecimal()) #True
# print(num3.isdecimal()) #False
# print(num4.isdecimal()) #False

#isnumeric:str,unicode,中文数字,罗马数字
# num0='4'
# num1=b'4' #bytes
# num2=u'4' #unicode,python3中无需加u就是unicode
# num3='四' #中文数字
# num4='Ⅳ' #罗马数字
#
# print(num0.isnumeric()) #True
# # print(num1)
# print(num2.isnumeric()) #True
# print(num3.isnumeric()) #True
# print(num4.isnumeric()) #True

# #三者不能判断浮点数
# num5='4.3'
# print(num5.isdigit())
# print(num5.isdecimal())
# print(num5.isnumeric())
# '''
# 总结:
# 最常用的是isdigit,可以判断bytes和unicode类型,这也是最常见的数字应用场景
# 如果要判断中文数字或罗马数字,则需要用到isnumeric
# '''


#is其他
# name='egon123'
# print(name.isalnum()) #字符串由字母和数字组成
# name='asdfasdfa sdf'
# print(name.isalpha()) #字符串只由字母组成

# name='asdfor123'
# print(name.isidentifier()) #True
# name='egGon'
# print(name.islower()) #False
# # print(name.isupper()) #False
# # print(name.isspace()) #False
# name='Egon say'
# print(name.istitle()) #False
posted @ 2017-07-19 17:31  Cool·  阅读(167)  评论(0编辑  收藏  举报