A string that defines a variable in python
str1 = "www" #str1 is a string, must use quotation marks
Or directly use "string." to call the internal method
1. String case operation
capitalize() method - capitalize at the beginning
print('wsy www'.capitalize())
Wsy www
swapcase() method - all caps
print("wsy ada".swapcase())
WSY ADA
isupper() method - return True or Flase to determine whether all uppercase is uppercase
print ( 'AAA' .isupper()) #Whether they are all uppercase
True
islower() method - to determine whether all lowercase returns True or Flase
print('a,1,a'.islower())
True
upper() method - all uppercase
print('wSy'.upper())
WSY
lower() method - all lowercase
print('wSy'.lower())
wsy
title() method - space-separated first letters are capitalized
print('wsy ww'.title())
Wsy Ww
istitle() method - determine whether the first letter is capitalized by space separation
print('My Name Is '.istitle())
True
replace() method - replace lowercase with uppercase, replace x
print ( 'wsy' .replace( 's' , 'S' , 1 )) #replace one
wSy
2. Passing parameters
format() format_map() parameter
name = "wsy www {w} {s}"
print(name.format(w="1",s=11))
print(name.format_map({'w':'1','s':'11'}))
wsy www 1 11
3. Print, complete, convert
count() prints the number of specified characters
print('name'.count("n"))
1
center() prints x characters that are not enough to complete with y, and the characters are centered
print('name'.center(50,"-"))
-----------------------name-----------------------
ljust() prints characters of length x not enough to append with y padding
print ( 'name' .ljust ( 50 , '*' ))
name**********************************************
rjust() prints characters of length x not enough to fill the start with y
print('name'.rjust(50,'*'))
**********************************************name
zfill() prints characters of length x not enough to fill with 0
print('wsywsywsy'.zfill(20))
00000000000wsywsywsy
expandtabs() converts tab keys to x spaces
print ('nam \ te'.expandtabs (tabsize = 30))
for e
find() returns that the starting subscript of the search string is not -1
print('name'.find("na"))
0
rfind() returns the last character subscript of the search string is not -1
print('wsywangsiyu'.rfind('y'))
9
['zifuchuan'.find("a"):] String slice from x to end
print('wsy'['wsy'.find("s"):])
his
join() list to string
print(''.join(['1','2','3','4']))
1234
strip() removes trailing spaces and carriage returns
print('wsy\n'.strip())
wsy
lstrip() removes leading spaces and carriage returns
print('\n wsy'.lstrip())
wsy
split() is separated into a list according to the specified character, the default space
print ( '.swit .s y' .split ())
print ( 'Ww_sy .ws y' .split ( 's' ))
['ww_sy', '.ws', 'y']
['ww_', 'y .w', ' y']
splitlines() separates a list by newline
print('1234\n 123'.splitlines())
['1234', ' 123']
translate() its own encryption must correspond to the number before and after
p = str.maketrans("abcdef","123456")print("abeeee".translate(p))
125555
4. Judgment
name = 'www'
print(name.endswith('sy')) #Judging whether the end result of the specified string is true or false
print(name.isalnum()) #Contains English and Arabic characters without special characters and returns True
print('nameA'.isalpha( )) #Determine whether it is a pure English character
print(name.isdecimal()) #Whether it is an integer
print('1A'.isidentifier()) #Determine whether it is a legal identifier (variable name)
print('0'. isnumeric( ) ) #Determine whether it is a natural number#
print(' '.isspace()) #Is it a space
print('My name is '.isprintable()) #Whether it can print tty drive
False
True
True
False
False
True
True
True