title()
Role: The first letter of a string of English words in all uppercase
eg：
>>> test1 = ' my name is Alex'
>>> print(test1.title())
My Name Is Alex
strip()
Role: delete the beginning and end of the string all the special characters "\ n, \ r"
eg：
>>> test = "\n \n \n hello honey \n xixi \n nishi \n djaoifa \n"
>>> print(test.strip())
hello honey
xixi
nishi
djaoifa
lower()
Role: Converts a string in all lowercase English words
eg：
>>> test1 = 'my Name iS Alex'
>>> print(test1.lower())
my name is alex
upper()
Role: to convert a string of all English words to uppercase
eg：
>>> test1 = ' My Name iS Alex'
>>> print(test1.upper())
MY NAME IS ALEX
center()
Action: the left and right in the middle of the string and the number of characters specified
eg：
>>> test1 = ' i Name iS Alex'
>>> print(test1.center(40,"-"))
------------ i Name iS Alex------------
light()
Role: left-aligned, not enough can use other supplements
eg：
>>> test1 = ' i Name iS Alex'
>>> test2 = 'dadaddada'
>>> print(test1.ljust(40,"-"))
>>> print(test1.ljust(40))
>>> print(test2.ljust(40,"*"))
i Name iS Alex------------------------
i Name iS Alex
dadaddada*******************************
rjust ()
Role: right-aligned, not enough can use other supplements
eg：
>>> test1 = ' i Name iS Alex'
>>> test2 = 'dadaddada'
>>> print(test1.rjust(40,"-"))
>>> print(test1.rjust(40))
>>> print(test2.rjust(40,"*"))
---------------------------- i Name iS Alex
i Name iS Alex
*******************************dadaddada
count()
: The role of the number of characters appear in statistics
eg：
>>> test1 = 'this is test'
>>> print(test1.count("t"))
>>> print(test1.count("t",0,10))
3
2
encode()
Role: to solve the problem of decoding
eg：
Test1 = >>> 'the this Test IS'
>>> = test2 'This is a test'
>>> Print (test1.encode (encoding = 'UTF8', errors = 'sreict'))
>>> Print (test2. encode (encoding = 'utf8', errors = 'sreict'))
Is test b'this'
b '\ xe8 \ XBF \ x99 \ xe6 \ x98 \ XAF \ xe4 \ xb8 \ x80 \ xe4 \ xb8 \ XAA \ xe6 \ xb5 \ x8b \ xe8 \ XAF \ X95'
decode()
Role: resolve character encoding issues
eg：
>>> test1 = 'this is test'
>>> test2 = '这是一个测试'
>>> str1 = test1.encode(encoding='utf8',errors='sreict')
>>> str2 = test2.encode(encoding='utf8',errors='sreict')
>>> print(str1.decode(encoding='utf8',errors='sreict'))
>>> print(str2.decode(encoding='utf8',errors='sreict'))
this is test
this is a test
find()
Role: return to find the index of the string
Find the opposite direction "rfind ()"
eg：
>>> test1 = 'this is test'
>>> print(test1.find("i"))
>>> print(test1.find("i",4))
>>> print(test1.find("0"))
2
5
-1
format()
Action: Returns a formatted string
eg：
>>> test1 = '{first} this is {number} test'
>>> print(test1.format(first="teststring",number="python"))
teststring this is python test
endswith()
Role: to determine whether the string ends with the specified character
eg：
>>> test1 = 'this is test'
>>> print(test1.endswith("python"))
>>> print(test1.endswith("test"))
False
True
startswith()
Role: to determine whether the string beginning at a specified character
eg：
>>> test1 = 'this is test'
>>> print(test1.startswith("python"))
>>> print(test1.startswith("this"))
False
True
isalnum ()
Action: determining whether a string of numbers and letters
eg：
>>> test1 = 'thisistest123123'
>>> test2 = 'this is test 123 #$#$#$'
>>> print(test1.isalnum())
>>> print(test2.isalnum())
True
False
Islf ()
Action: detecting whether a string consisting only of letters
eg：
>>> test1 = 'thisistest123123'
>>> test2 = 'thisistest'
>>> print(test1.isalpha())
>>> print(test2.isalpha())
False
True
isdigit()
Action: detecting whether a string consisting only of numbers
eg：
>>> test1 = 'thisistest123123'
>>> test2 = '123412312341'
>>> print(test1.isdigit())
>>> print(test2.isdigit())
False
True
islower()
The role: whether all lowercase letters
eg：
>>> test1 = 'thisistest'
>>> test2 = 'Tasdasd123'
>>> print(test1.islower())
>>> print(test2.islower())
True
False
isupper()
The role: whether all uppercase letters
eg：
>>> test1 = 'thisistest'
>>> test2 = 'THISAHHA123'
>>> print(test1.isupper())
>>> print(test2.isupper())
False
True
ispace()
Role: detecting whether or not constituted only by spaces
eg：
>>> test1 = ' '
>>> test2 = 'THISAHHA123'
>>> print(test1.isspace())
>>> print(test2.isspace())
True
False
partition()
Action: dividing a specified character, returns a tuple
From right to left "rpartition ()"
eg：
Str = >>> "https://www.baidu.com/"
>>> Print (str.rpartition ( ": //"))
>>> Print (str.rpartition ( ",")) # string str sep absence of ",", two returns an empty string
('https', '://', 'www.baidu.com/')
('', '', 'https://www.baidu.com/')
split()
Action: to split the specified character string as a split return a list character
Instead "rsplit ()"
eg：
Str1 = >>> "https://www.baidu.com/"
>>> str2 = "I do Not Love Python"
>>> Print (str1.split ( "."))
>>> Print (str2. split ()) # is the default does not write blank
['https://www', 'baidu', 'com/']
['i', 'do', 'not', 'love', 'python']
splitlines()
Action: In \ n and \ r as the dividing delimiter strings, "True" parameter display symbols
eg：
>>> str1 = """i
love
python
"""
>>> print(str1.splitlines())
>>> print(str1.splitlines(True))
['i', 'love', 'python']
['i\n', 'love\n', 'python\n']
join()
Action: The character string entered as the number of elements and between each element in the list, and form a new series of strings,
>>> list1 = ["abc","123","test","aadadad"]
>>> str1 = "*python*"
>>> print(str1.join(list1))
python abc * * 123 * * the test python python * * aadadad
replace()
Action: The specified character string is replaced with a new character
Str1 = >>> "My My Happ adasdmy the Test"
>>> Print (str1.replace ( "My", "# # Python"))
>>> Print (str1.replace ( "My", "# # Python" , 1)) # You can specify the number of replacement
#python# #python# happ adasd#python# test
#python# my happ adasdmy test
