A complete collection of Python string manipulation methods

A large collection of Python string operation methods, including almost all commonly used Python string operations, such as string replacement, deletion, interception, copy, connection, comparison, search, split, etc. Friends who need it can refer to it


1. Remove spaces and special symbols


Copy the code as follows:

s.strip().lstrip().rstrip(',')

2. Copy the string

Copy the code as follows:

#strcpy(sStr1,sStr2)
sStr1 = 'strcpy'
sStr2 = sStr1
sStr1 = 'strcpy2'
print sStr2

3. Connection string

Copy the code as follows:

#strcat(sStr1,sStr2)
sStr1 = 'strcat'
sStr2 = 'append'
sStr1 += sStr2
print sStr1

4. Find the character

Copy the code as follows:

#strchr(sStr1,sStr2)
# sStr1 = 'strchr'
sStr2 = 's'
nPos = sStr1.index(sStr2)
print nPos

5. Compare strings

Copy the code as follows:

#strcmp(sStr1,sStr2)
sStr1 = ' strchr'
sStr2 = 'strch'
print cmp(sStr1,sStr2)

6. Scan whether the string contains the specified characters

Copy the code as follows:

#strspn(sStr1,sStr2)
sStr1 = '12345678'
sStr2 = '456'
#sStr1 and chars both in sStr1 and sStr2
print len(sStr1 and sStr2)

7. String length

Copy the code as follows:

#strlen(sStr1)
sStr1 = 'strlen '
print len(sStr1)

8. Convert the case in the string

Copy the code as follows:

S.lower() #lowercase
S.upper() #uppercase
S.swapcase() # Case swap
S.capitalize() #Capitalize the first letter
String.capwords(S) #This is a method in the module. It separates S using the split() function, then uses capitalize() to capitalize the first letter, and finally uses join() to merge them together
#Example:
#strlwr(sStr1)
sStr1 = 'JCstrlwr'
sStr1 = sStr1 .upper()
#sStr1 = sStr1.lower()
print sStr1


9. Append a string of specified length

Copy the code as follows:

#strncat(sStr1,sStr2,n)
sStr1 = '12345 '
sStr2 = 'abcdef'
n = 3
sStr1 += sStr2[0:n]
print sStr1

10. String specified length comparison

Copy the code as follows:

#strncmp(sStr1,sStr2,n )
sStr1 = '12345'
sStr2 = '123bc'
n = 3
print cmp(sStr1[0:n],sStr2[0:n])

11. Copy characters of the specified length

Copy code The code is as follows :

#strncpy(sStr1,sStr2,n)
sStr1 = ''
sStr2 = '12345'
n = 3
sStr1 = sStr2[0:n]
print sStr1

12. Change the first n characters of the string Replace with the specified characters

Copy the code as follows:

#strnset(sStr1,ch,n)
sStr1 = '12345'
ch = 'r'
n = 3
sStr1 = n * ch + sStr1[3: ]
print sStr1

13. Scan the string

Copy the code as follows:

#strpbrk(sStr1,sStr2)
sStr1 = 'cekjgdklab'
sStr2 = 'gka'
nPos = -1
for c in sStr1:
if c in sStr2: nPos = sStr1.index(c)
print nPos

14. Flip the string

Copy the code as follows:

#strrev(sStr1)
sStr1 = 'abcdefg '
sStr1 = sStr1[::-1]
print sStr1

15. Find the string

Copy the code. The code is as follows:

#strstr(sStr1,sStr2)
sStr1 = 'abcdefg'
sStr2 = 'cde'
print sStr1.find (sStr2)

16. Split the string

Copy the code as follows:

#strtok(sStr1,sStr2)
sStr1 = 'ab,cde,fgh,ijk'
sStr2 = ','
sStr1 = sStr1[sStr1 .find(sStr2) + 1:]
print sStr1
#or
s = 'ab,cde,fgh,ijk'
print(s.split(','))

17. Connection string

Copy code The code is as follows:

delimiter = ','
mylist = ['Brazil', 'Russia', 'India', 'China']
print delimiter.join(mylist)

18. Implementation of addslashes in PHP

Copy The code is as follows:

def addslashes(s):
d = {'"':'\"', "'":"\'", "# The encoding can have multiple values, such as gb2312 gbk gb18030 bz2 zlib big5 bzse64, etc. are supported. The default value of errors is "strict", which means UnicodeError. Possible values ​​are 'ignore', 'replace', 'xmlcharrefreplace', 'backslashreplace' and all values ​​registered via codecs.register_error. This part of the content involves the codecs module, which is not very clear
S.decode([encoding,[errors]])

26. String testing and judgment functions. This type of function does not exist in the string module. These functions return It is a bool value

Copy the code as follows:

S.startswith(prefix[,start[,end]])
#Whether it starts with prefix
S.endswith(suffix[,start[,end]])
#With The end of suffix
S.isalnum()
#Is it all letters and numbers, and at least one character?
S.isalpha() #Is it all letters, and at least one character?
S.isdigit() #Is it all numbers? , and have at least one character
S.isspace() #Whether they are all blank characters, and have at least one character
S.islower() #Whether the letters in S are all lowercase
S.isupper() #The letters in S Is it capitalized
S.istitle() #Is S the first letter capitalized?

27. String type conversion functions, these functions are only available in the string module

Copy the code as follows:

string.atoi (s[,base])
#base defaults to 10. If it is 0, then s can be a string in the form of 012 or 0x23. If it is 16, then s can only be a character in the form of 0x23 or 0X12. String
string.atol(s[,base]) #Convert to long
string.atof(s[,base]) #Convert to float


I emphasize again that string objects are immutable, that is to say After creating a string in python, you cannot change a certain part of the characters. After any of the above functions changes the string, it will return a new string, and the original string has not changed. In fact, there is a workaround for this. You can use the S=list(S) function to turn S into a list with a single character as a member. In this case, you can use S[3]='a' to change the value, and then Then use S=" ".join(S) to restore it to a string