Tutorial on the use of str (string) in python3

This article mainly introduces the operation summary of python3 to str (string). It is very detailed in this article. Let's have a look at it if you need it.

S 5en__ function (append the string later)

s1 ='Hello'
s2 = s1.__add__(' boy!')
print(s2)

# Output: Hello boy!

S. S. S. S. S. S. S. S. S. S. S. S.

s1 = 'Hello'
result = s1.__contains__('He')
print(result)

# Output: True

S. S. S. S. S. S. S. S. S. S. S. S.

s1 = 'Hello'
s2 = 'How'
result = s1.__eq__(s2)
print(result)

# Output: False

__format__

# placeholder 

__getattribute__

# placeholder 

__getitem__

# placeholder 

__getnewargs__

# placeholder 

S = s = s = s = s = s

print('b'.__ge__('a'))

# Output: True

__gt__ (greater than)

print('b'.__ge__('a'))

# Output: True

__hash__

# placeholder 

__iter__

s1 = 'Hello'
result = s1.__contains__('He')
print(result)

# Output: True

0

S 51en__ (return string length)

print('abc'.__len__())

# Output: 3

S 55en__ (less than or equal to)

print('b'.__le__('a'))

# Output: False

S 59en__ (less than)

s1 = 'Hello'
result = s1.__contains__('He')
print(result)

# Output: True

3

__mod__

s1 = 'Hello'
result = s1.__contains__('He')
print(result)

# Output: True

4

__mul__

s1 = 'Hello'
result = s1.__contains__('He')
print(result)

# Output: True

5

__new__

s1 = 'Hello'
result = s1.__contains__('He')
print(result)

# Output: True

6

__ne__

s1 = 'Hello'
result = s1.__contains__('He')
print(result)

# Output: True

7

__repr__

s1 = 'Hello'
result = s1.__contains__('He')
print(result)

# Output: True

8

__rmod__

s1 = 'Hello'
result = s1.__contains__('He')
print(result)

# Output: True

9

__rmul__

# placeholder 

__sizeof__

# placeholder 

S 95en__ (return to self)

print('abc'.__str__())

# Output: abc

capitalize(capital letters)

s = 'tom'
print(s.capitalize())

# Output: Tom

casefold (uppercase to lowercase)

s = 'TOM'
print(s.casefold())

# Output: tom

center (specify length and padding characters, center the content, and space for padding characters)

s = 'Tom'
print(s.center(20,'-'))

# Output: --------Tom---------

count(count the number of occurrences of a string, parameter 2: start position, parameter 3: end position)

s1 = 'Hello'
s2 = 'How'
result = s1.__eq__(s2)
print(result)

# Output: False

6

encode (encoding)

s1 = 'Hello'
s2 = 'How'
result = s1.__eq__(s2)
print(result)

# Output: False

7

endswith (second argument to determine whether a string ends with a character or string: start position, third argument: end position)

s1 = 'Hello'
s2 = 'How'
result = s1.__eq__(s2)
print(result)

# Output: False

8

expandtabs (convert 1 tab key to 7 Spaces)

s1 = 'Hello'
s2 = 'How'
result = s1.__eq__(s2)
print(result)

# Output: False

9

find (find the index position of a character or string, parameter 2: start position, parameter 3: end position)

s = 'Hello'
print(s.find('o'))
print(s.find('o',0,3)) # Unable to return -1

# Output: 4
# -1

format(string formatting/concatenation)

# placeholder 

1

format_map

# placeholder 

2

index (looking for the index position of a character or string, like find, if the character does not exist, an error is reported)

# placeholder 

3

isalnum(whether letters or Numbers)

# placeholder 

4

isalpha(whether letter or not)

# placeholder 

5

isdecimal (whether it is a decimal number)

# placeholder 

6

isdigit (whether it is a number)

# placeholder 

7

isidentifier (whether identifier/variable name)

# placeholder 

8

islower (all lowercase)

s = 'Hello'
print(s.islower())

# Output: False

isnumeric (whether it is a number)

# placeholder 

0

isprintable(printable characters or not)

# placeholder 

1

isspace (whether space or not)

# placeholder 

2

istitle (whether to capitalize the title/the first letter of each word)

# placeholder 

3

isupper (all uppercase)

# placeholder 

4

join(concatenates the elements of a sequence to generate a new string with the specified characters)

# placeholder 

5

ljust(specify length and fill characters, content left aligned, fill characters left blank as Spaces)

# placeholder 

6

lower (all strings in lowercase)

# placeholder 

7

lstrip(removes the character specified to the left of the string, defaults to space)

# placeholder 

8

maketrans(create a conversion table for character mapping, used in conjunction with the translate function)

# placeholder 

9

partition (specify the separator to split the string)

# placeholder 

0

replace(replace old (the old string) in the string with new(the new string), and if the third parameter max is specified, replace it no more than max times.)

# placeholder 

1

rfind(looks for the location where the specified string appears from the right, and returns -1 if there is no match)

# placeholder 

2

rindex(find the location where the specified string appears from the right, and report an error if there is no match)

# placeholder 

3

rjust(specifies length and padding characters, right-aligned content, padding characters left blank as Spaces)

# placeholder 

4

rpartition (specify the delimiter to split the string from the right)

# placeholder 

5

rsplit(specify the separator to slice the string, if the second parameter num is specified, num is separated only once, and 1 list is returned)

# placeholder 

6

rstrip(removes the specified character at the end of the string, defaults to space)

s = '!!! I am Tom !!!'
print(s.rstrip('!'))

# Output: !!! I am Tom

split(specify the delimiter to slice the string, if the second parameter num is specified, num is separated only once, and 1 list is returned)

s = 'a b c d'
print(s.split())
print(s.split(' ',2)) # Start on the left and space it twice 

# Output: ['a', 'b', 'c', 'd']
# ['a', 'b', 'c d']

splitlines(returns 1 list, delimited by newline)

# placeholder 

9

startswith (second argument to determine whether a string begins with a character or string: start position, third argument: end position)

# placeholder 

0

strip(specified characters before and after deletion of string, default to space)

# placeholder 

1

swapcase (case interchange)

# placeholder 

2

title(converted to title, which is the first letter of each word in uppercase)

# placeholder 

3

translate (character substitution according to the table created by the maketrans method)

# placeholder 

4

upper(lowercase to uppercase)

# placeholder 

5

zfill(specifies the length of the string. Align the original string to the right, fill in 0 in front)

s = 'Hello'
print(s.zfill(10))

#  Output: 00000Hello

conclusion