Python string built-in functions

Python's string commonly built-in functions are as follows:

Serial Number	Method and Description
1	Capitalize ()      Convert the first character of a string to uppercase # !/usr/bin/python3 str = " this is a string example from Runoob....wow!!! " print ( " str.capitalize (): " is string example from runoob....wow!!!
2	Center (width, Fillchar) Returns a string that specifies the width of the center, Fillchar is a filled character, and the default is a space. # !/usr/bin/python3 "[www.runoob.com]"print ("" " * ' ) The result of the above example output is as follows: Str.center ('*'): ************[www.runoob.com]*** *********
3	Count (str, beg= 0,end=len (String)) Returns the number of occurrences of STR in a string, if beg or end specifies that the number of STR occurrences in the specified range is returned #!/usr/bin/python3Str="www.runoob.com"Sub='o'Print("str.count (' O '):", Str.count (sub)) Sub='Run'Print("str.count (' run ', 0, ten):", Str.count (sub,0,10)) The output of the above example is as follows: Str.count ('o'): 3Str.count ('Run', 0, 10): 1
4	Bytes.decode (encoding= "Utf-8", errors= "strict") There is no Decode method in Python3, but we can use the decode () method of the Bytes object to decode the given bytes object, which can be encoded back by bytes (). #!/usr/bin/python3Str="Beginner's Tutorial"; Str_utf8= Str.encode ("UTF-8") STR_GBK= Str.encode ("GBK")Print(str)Print("UTF-8 Code:", Str_utf8)Print("GBK Code:", STR_GBK)Print("UTF-8 decoding:", Str_utf8.decode ('UTF-8','Strict'))Print("GBK decoding:", Str_gbk.decode ('GBK','Strict') ) The above example output is as follows: Rookie tutorial UTF-8 Code: b'\xe8\x8f\x9c\xe9\xb8\x9f\xe6\x95\x99\xe7\xa8\x8b'GBK code: B'\XB2\XCB\XC4\XF1\XBD\XCC\XB3\XCC'UTF-8decoding: Rookie tutorial GBK decoding: Rookie tutorial
5	Encode (encoding= ' UTF-8 ', errors= ' strict ') Encodes a string in the encoded format specified by encoding, if an error defaults to a ValueError exception unless errors specifies ' ignore ' or ' replace ' #!/usr/bin/python3Str="Beginner's Tutorial"; Str_utf8= Str.encode ("UTF-8") STR_GBK= Str.encode ("GBK")Print(str)Print("UTF-8 Code:", Str_utf8)Print("GBK Code:", STR_GBK)Print("UTF-8 decoding:", Str_utf8.decode ('UTF-8','Strict'))Print("GBK decoding:", Str_gbk.decode ('GBK','Strict') ) The above example output is as follows: Rookie tutorial UTF-8 Code: b'\xe8\x8f\x9c\xe9\xb8\x9f\xe6\x95\x99\xe7\xa8\x8b'GBK code: B'\XB2\XCB\XC4\XF1\XBD\XCC\XB3\XCC'UTF-8decoding: Rookie tutorial GBK decoding: Rookie tutorial
6	EndsWith (suffix, beg=0, End=len (String)) Checks whether the string ends with obj, or returns False if beg or end specifies whether to end with obj in the specified range, or True if it is. # !/usr/bin/python3 str =" runoob example .... WOW!!! " suffix = " !! " print (str.endswith (suffix)) print (Str.endswith (Suffix,20 = " run " print (str.endswith (suffix)) print (str.endswith (suffix, 0, 19
7	Expandtabs (tabsize=8) Turns the tab symbol in string strings to a space, and the default number of spaces for the tab symbol is 8. #!/usr/bin/python3Str="This is\tstring example....wow!!!"Print("Original string:"+str)Print("Replace the \\t symbol:"+str.expandtabs ())Print("Replace the \\t symbol with 16 spaces:"+ Str.expandtabs (16)) The output of the above example is as follows: Raw string: This isstring EXAMPLE....WOW!!! Replace the \ t symbol: this isstring EXAMPLE....WOW!!! Replace the \ t symbol with 16 spaces: This isString EXAMPLE....WOW!!!
8	Find (str, beg=0 End=len (String)) Detects if STR is contained in a string, and if the range beg and end is specified, the check is contained within the specified range and returns 1 if it contains the index value that returns the start.
9	Index (str, beg=0, End=len (String)) Just like the Find () method, only if STR does not report an exception in the string.
10	Isalnum () Returns True if the string has at least one character and all characters are letters or numbers, otherwise False
11	Isalpha () Returns True if the string has at least one character and all characters are letters, otherwise False
12	IsDigit () Returns True if the string contains only a number, otherwise False:
13	Islower () Returns True if the string contains at least one case-sensitive character, and all of these (case-sensitive) characters are lowercase, otherwise False
14	IsNumeric () Returns True if the string contains only numeric characters, otherwise False
15	Isspace () Returns True if the string contains only white space, otherwise False.
16	Istitle () Returns True if the string is heading (see Title ()), otherwise False
17	Isupper () Returns True if the string contains at least one case-sensitive character, and all of these (case-sensitive) characters are uppercase, otherwise False
18	Join (SEQ) Merges all elements of the SEQ (the string representation) into a new string with the specified string as a delimiter
19	Len (String) return string length
20	Ljust (width[, Fillchar]) Returns a string that is left-justified by using Fillchar to fill a new string of length width, and fillchar the default is a space.
21st	Lower () Converts all uppercase characters in a string to lowercase.
22	Lstrip () Truncates the left space of the string or specifies the character.
23	Maketrans () To create a conversion table of character mappings, for the simplest invocation of two parameters, the first argument is a string representing the character that needs to be converted, and the second argument is the target of the string representation of the transformation.
24	Max (str) Returns the largest letter in the string str.
25	Min (str) Returns the smallest letter in the string str.
26	Replace (old, new [, Max]) Replace the str1 in the string with str2, and if Max specifies it, the replacement does not exceed Max times.
27	RFind (str, Beg=0,end=len (String)) Similar to the Find () function, it is just looking from the right.
28	Rindex (str, beg=0, End=len (String)) Similar to index (), but starting from the right.
29	Rjust (width,[, Fillchar]) Returns the right alignment of an original string and fills a new string of length width with Fillchar (default space)
30	Rstrip () Removes a space at the end of a string string.
31	Split (str= "", Num=string.count (str)) Num=string.count (str)) intercepts a string with the Str delimiter, and only the NUM substring if NUM has a specified value
32	Splitlines ([keepends]) Separated by rows (' \ r ', ' \ r \ n ', \ n '), returns a list containing the rows as elements, if the argument keepends is False, does not contain a newline character, and if true, the newline character is preserved.
33	StartsWith (str, Beg=0,end=len (String)) Checks whether the string starts with obj, returns True, or False. If beg and end specify a value, the check is within the specified range.
34	Strip ([chars]) Execute Lstrip () and Rstrip () on a string
35	Swapcase () Convert uppercase in a string to lowercase, lowercase to uppercase
36	Title () Returns the "heading" string, meaning all words start with uppercase and the remaining letters are lowercase (see istitle ())
37	Translate (table, deletechars= "") Converts a string character to a table (containing 256 characters) given by STR, and the character to be filtered out into the Deletechars parameter
38	Upper () lowercase letters in a converted string are capitalized
39	Zfill (width) Returns a string of length width, the original string right-aligned, front padding 0
40	Isdecimal () Checks whether the string contains only decimal characters and returns False if true.

Python string built-in functions