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