python字符串内置方法[通俗易懂]

大家好，又见面了，我是你们的朋友全栈君。

字符串的内置方法(部分)

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

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

# print(msg.lstrip('*'))
# print(msg.rstrip('*'))

#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))

#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




# 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'))
# 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'))


# name='goee 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('S')) #同上,但是找不到会报错
#
# print(name.count('S',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))


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