Python之字符串的134个常用操作_abab4546

一、字符串切片操作

test = "Python Programming"
print("String: ", test)
 
# First one character
first_character = test[:1]
print("First Character: ", first_character)
 
# Last one character
last_character = test[-1:]
print("Last Character: ", last_character)
 
# Everything except the first one character
except_first = test[1:]
print("Except First Char.: ", except_first)
 
# Everything except the last one character
except_last = test[:-1]
print("Except First Char.: ", except_last)
 
# Everything between first and last two character
between_two = test[2:-2]
print("Between two character: ", between_two)
 
# Skip one character
skip_one = test[0:18:2]  # [start:stop:step]
print("Skip one character: ", skip_one)
 
# Reverse String
reverse_str = test[::-1]
print("Reverse String: ", reverse_str)
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• 执行结果：

String:  Python Programming
First Character:  P
Last Character:  g
Except First Char.:  ython Programming
Except First Char.:  Python Programmin
Between two character:  thon Programmi
Skip one character:  Pto rgamn
Reverse String:  gnimmargorP nohtyP
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二、检查字符串是否为空

import re
from collections import Counter
 
sentence = 'Canada is located in the northern part of North America'
# Example I
counter = len(re.findall("a", sentence))
print(counter)
 
# Example II
counter = sentence.count('a')
print(counter)
 
# Example III
counter = Counter(sentence)
print(counter['a'])
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• 执行结果：

Empty
Empty
Empty
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三、计算字符串中字符出现次数的多种方法

import re
from collections import Counter
 
sentence = 'Canada is located in the northern part of North America'
# Example I
counter = len(re.findall("a", sentence))
print(counter)
 
# Example II
counter = sentence.count('a')
print(counter)
 
# Example III
counter = Counter(sentence)
print(counter['a'])
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• 执行结果：

6
6
6
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四、将 String 变量转换为 float、int 或 boolean

# String to Float
float_string = "254.2511"
print(type(float_string))
 
string_to_float = float(float_string)
print(type(string_to_float))
 
# String to Integer
int_string = "254"
print(type(int_string))
 
string_to_int = int(int_string)
print(type(string_to_int))
 
 
# String to Boolean
bool_string = "True"
print(type(bool_string))
 
string_to_bool = bool(bool_string)
print(type(string_to_bool))
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• 执行结果：

class 'str'
class 'float>
class 'str'
class 'int'
class 'str'
class 'bool'
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五、向字符串填充或添加零的不同方法

num = 7
 
print('{0:0>5d}'.format(num))  # left
print('{0:0<5d}'.format(num))  # right
 
print('{:05d}'.format(num))
 
print("%0*d" % (5, num))
print(format(num, "05d"))
 
temp = 'test'
print(temp.rjust(10, '0'))
print(temp.ljust(10, '0'))
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• 执行结果：

00007
70000
00007
00007
00007
000000test
test000000
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7

六、去掉字符串中的 space 字符

string_var = "  \t a string example\n\t\r  "
print(string_var)
 
string_var = string_var.lstrip()  # trim white space from left
print(string_var)
 
string_var = "  \t a string example\t  "
string_var = string_var.rstrip()  # trim white space from right
print(string_var)
 
string_var = "  \t a string example\t  "
string_var = string_var.strip()  # trim white space from both side
print(string_var)
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• 执行结果：

     a string example
a string example
  	 a string example
a string example
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七、生成 N 个字符的随机字符串

import string
import random

def string_generator(size):
    chars = string.ascii_uppercase + string.ascii_lowercase
    return ''.join(random.choice(chars) for _ in range(size))
 
def string_num_generator(size):
    chars = string.ascii_lowercase + string.digits
    return ''.join(random.choice(chars) for _ in range(size))
 
# Random String
test = string_generator(10)
print(test)
 
# Random String and Number
test = string_num_generator(15)
print(test)
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• 执行结果：

acpPTojXet
qmpah72cjb83eqd
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八、以不同的方式反转字符串

test_string = 'Python Programming'
 
string_reversed = test_string[-1::-1]
print(string_reversed)
 
string_reversed = test_string[::-1]
print(string_reversed)
 
# String reverse logically
def string_reverse(text):
    r_text = ''
    index = len(text) - 1
 
    while index >= 0:
        r_text += text[index]
        index -= 1
 
    return r_text
 
print(string_reverse(test_string))
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• 执行结果：

gnimmargorP nohtyP

gnimmargorP nohtyP

gnimmargorP nohtyP
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九、将 Camel Case 转换为 Snake Case 并更改给定字符串中特定字符的大小写

import re

def convert(oldstring):
    s1 = re.sub('(.)([A-Z][a-z]+)', r'\1_\2', oldstring)
    return re.sub('([a-z0-9])([A-Z])', r'\1_\2', s1).lower()
 
# Camel Case to Snake Case
print(convert('CamelCase'))
print(convert('CamelCamelCase'))
print(convert('getHTTPResponseCode'))
print(convert('get2HTTPResponseCode'))
 
# Change Case of a particular character
text = "python programming"
result = text[:1].upper() + text[1:7].lower() \
    + text[7:8].upper() + text[8:].lower()
print(result)
 
text = "Kilometer"
print(text.lower())
 
old_string = "hello python"
new_string = old_string.capitalize()
print(new_string)
 
old_string = "Hello Python"
new_string = old_string.swapcase()
print(new_string)
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• 执行结果：

camel_case
camel_camel_case
get_http_response_code
get2_http_response_code
Python Programming
kilometer
Hello python
hELLO pYTHON
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十、检查给定的字符串是否是 Python 中的回文字符串

import re

Continue = 1
Quit = 2
 
def main():
    choice = 0
 
    while choice != Quit:
        # Display the menu.
        display_menu()
        # Constant to assume string is Palindrome
        is_palindrome = True
 
        # Get the user's choice.
        choice = int(input('\nEnter your choice: '))
 
        # Perform the selected action.
        if choice == Continue:
            line = input("\nEnter a string: ")
            str_lower = re.sub("[^a-z0-9]", "", line.lower())
            for i in range(0, len(str_lower)//2):
                if str_lower[i] != str_lower[len(str_lower) - i - 1]:
                    is_palindrome = False
 
            if is_palindrome:
                print(line, "is a palindrome")
            else:
                print(line, "is not a palindrome")
        else:
            print('Thank You.')
def display_menu():
    print('\n*******MENU*******')
    print('1) Continue')
    print('2) Quit')
main()
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• 执行结果：

*******MENU*******
1) Continue
2) Quit
Enter your choice: 1
Enter a string: A dog! A panic in a pagoda!
A dog! A panic in a pagoda! is a palindrome

*******MENU*******
1) Continue
2) Quit
Enter your choice: 1
Enter a string: Civic
Civic is a palindrome

*******MENU*******
1) Continue
2) Quit
Enter your choice: 1
Enter a string: Python vs Java
Python vs Java is not a palindrome

*******MENU*******
1) Continue
2) Quit
Enter your choice: 2
Thank You.
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十一、检查字符串是否以列表中的一个字符串结尾

str_list = ['aaa', 'bbb', 'ccc', 'ddd']  # list of items
str_test = 'testccc'  # string need to test
 
for str_item in str_list:
    if str_test.endswith(str_item):
        print("found")
        break   # loop ends when result found
    else:
        print("not found")
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• 执行结果：

not found
not found
found
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十二、在字符串中应用查找模式

import re

s1 = 'abccba'
s2 = 'abcabc'
s3 = 'canadajapanuaeuaejapancanada'
p = '123321'

def match(s, p):
    nr = {}
    regex = []
    for c in p:
        if c not in nr:
            regex.append('(.+)')
            nr[c] = len(nr) + 1
        else:
            regex.append('\\%d' % nr[c])
    return bool(re.match(''.join(regex) + '$', s))

print(match(s1, p))
print(match(s2, p))
print(match(s3, p))
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• 执行结果：

True
False
True
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十三、如果是 Python 中的反斜杠，则删除最后一个字符

x = 'China\\'
print(x.rstrip('\\'))
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• 执行结果：

China
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十四、拆分字符串而不丢失拆分字符

import re
string = 'China-Great-Country'

print(re.split(r'(\-)', string))
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• 执行结果：

['China', '-', 'Great', '-', 'Country']
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十五、从字符串 Python 中提取大写和小写字符

string = "asdfHRbySFss"

uppers = [l for l in string if l.isupper()]
print (''.join(uppers))

lowers = [l for l in string if l.islower()]
print (''.join(lowers))
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• 执行结果：

HRSF
asdfbyss
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十六、如何在 Python 中比较字符串的索引是否相等

myString = 'AAABBB'
for idx, char in enumerate(myString, ):
    if idx + 1 == len(myString):
        break
    if char == myString[idx + 1]:
        print(idx, char, myString[idx + 1])
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• 执行结果：

0 A A
1 A A
3 B B
4 B B
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十七、在每个第 4 个字符上添加空格

string = 'Test5412Test8745Test'
print([string[i:i + 4] for i in range(0, len(string), 4)])
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• 执行结果：

['Test', '5412', 'Test', '8745', 'Test']
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十八、在 Python 中以多行方式连接字符串

str1 = "This is a demo string"
str2 = "This is another  demo string"
strz = ("This is a line\n" +
       str1 + "\n" +
       "This is line 2\n" +
       str2 + "\n" +
       "This is line 3\n")

print(strz)
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• 执行结果：

This is a line
This is a demo string
This is line 2
This is another  demo string
This is line 3
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十九、在 Python 中将多个变量附加到列表中

volumeA = 100
volumeB = 20
volumeC = 10

vol1 = []
vol2 = []

vol1.extend((volumeA, volumeB, volumeC))
vol2 += [val for name, val in globals().items() if name.startswith('volume')]

print(vol1)
print(vol2)
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• 执行结果：

[100, 20, 10]
[100, 20, 10]
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二十、将字符串拆分为 Python 中的字符列表

s = 'China'
l = list(s)
print(l)
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• 执行结果：

['C', 'h', 'i', 'n', 'a']
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二十一、如何在 Python 中小写字符串

text = ['China', 'BEIJING']

text = [txt.lower() for txt in text]
print(text)
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• 执行结果：

['china', 'beijing']
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二十二、通过多个标点符号分割字符串

import re
s = 'a,b,c d!e.f\ncanada\tjapan&germany'
 
l = re.split('[?.,\n\t&! ]', s)
 
for i in l:
    print(i)
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• 执行结果：

a
b
c
d
e
f
canada
japan
germany
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二十三、Python 字符串填充

lines_of_text = [
    (123, 5487, 'Testing', 'Billy', 'Jones'),
    (12345, 100, 'Test', 'John M', 'Smith')
]

for mytuple in lines_of_text:
    name = '{}, {}'.format(mytuple[4], mytuple[3])
    value = '$' + str(mytuple[1])
    print('{name:<20} {id:>8} {test:<12} {value:>8}'.format(
        name=name, id=mytuple[0], test=mytuple[2], value=value)
    )
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• 执行结果：

Jones, Billy              123 Testing         $5487
Smith, John M           12345 Test             $100
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二十四、在 Python 中检查两个字符串是否包含相同的字符

str1 = 'caars'
str2 = 'rats'
str3 = 'racs'

print(set(str1)==set(str2))
print(set(str1)==set(str3))
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• 执行结果：

False
True
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二十五、在 Python 中查找给定字符串中的整个单词

def contains_word(s, w):
    return (' ' + w + ' ') in (' ' + s + ' ')

result = contains_word('those who seek shall find', 'find')
print(result)
result = contains_word('those who seek shall find', 'finds')
print(result)
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• 执行结果：

True
False
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二十六、查找所有出现的子字符串

import re

aString = 'this is a string where the substring "is" is repeated several times'
print([(a.start(), a.end()) for a in list(re.finditer('is', aString))])
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• 执行结果：

[(2, 4), (5, 7), (38, 40), (42, 44)]
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二十七、在 Python 中去除所有开头在Python中的正斜杠上拆分字符串和结尾标点符号

from string import punctuation
s = '.$958-5-China,#'

print(s.strip(punctuation))
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• 执行结果：

958-5-Canada
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二十八、用 Python 中的正斜杠上拆分字符串

s = 'China/Beijing/Tiananmen'
l = s.split('/')
 
print(l)
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• 执行结果：

['China', 'Beijing', 'Tiananmen']
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二十九、根据 Python 中的索引位置将字符串大写

def capitalize(s, ind):
    split_s = list(s)
    for i in ind:
        try:
            split_s[i] = split_s[i].upper()
        except IndexError:
            print('Index out of range : ', i)
    return "".join(split_s)


print(capitalize("abracadabra", [2, 6, 9, 10, 50]))
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• 执行结果：

Index out of range :  50
abRacaDabRA
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三十、检查字符串中的所有字符是否都是 Python 中的数字

a = "1000"
x = a.isdigit()
print(x)

b = "A1000"
x = b.isdigit()
print(x)
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• 执行结果：

True
False
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三十一、为什么使用’=='或’is’比较字符串有时会产生不同的结果

a = 'abcdef'
b = ''.join(['ab', 'cd', 'ef'])
print(a == b)
print(a is b)

a = [1, 2, 3]
b = [1, 2, 3]
print(a == b)
print(a is b)

c = b
print(c is b)
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• 执行结果：

True
False
True
False
True
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三十二、如何在 Python 中为字符串添加 X 个空格

print('China'.ljust(10) + 'Beijing'.ljust(20) + 'Tiananmen')
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• 执行结果：

China    Beijing               Tiananmen
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三十三、如何在 Python 中替换字符串中的特定字符串实例

def nth_replace(str,search,repl,index):
    split = str.split(search,index+1)
    if len(split)<=index+1:
        return str
    return search.join(split[:-1])+repl+split[-1]

str1 = "caars caars caars"
str2 = nth_replace(str1, 'aa', 'a', 1)

print(str2)
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• 执行结果：

caars cars caars
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三十四、如何连接两个变量，一个是字符串，另一个是 Python 中的 int

int1 = 10
str1 = 'test'

print(str(int1) + str1)
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• 执行结果：

10test
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三十五、在 Python 中的反斜杠上拆分字符串

s = r'China\Beijing\Tiananmen'
l = s.split('\\')

print(l)
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• 执行结果：

['r'China', 'Beijing', 'Tiananmen']
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三十六、在 Python 中随机大写字符串中的字母

from random import choice

x = "China Beijing Tiananmen"
print(''.join(choice((str.upper, str.lower))(c) for c in x))
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• 执行结果：

ChiNA BeiJING TIANanMEn
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三十七、在单词处拆分字符串并且或不保留分隔符

import re

string = "Canada AND Japan NOT Audi OR BMW"

l = re.split(r'(AND|OR|NOT)', string)
print(l)
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• 执行结果：

['Canada ', 'AND', ' Japan ', 'NOT', ' Audi ', 'OR', ' BMW']
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三十八、在 Python 中填充 n 个字符

def header(txt: str, width=30, filler='*', align='c'):
    assert align in 'lcr'
    return {'l': txt.ljust, 'c': txt.center, 'r': txt.rjust}[align](width, filler)
 
 
print(header("Canada"))
print(header("Canada", align='l'))
print(header("Canada", align='r'))
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• 执行结果：

************Canada************
Canada************************
************************Canada
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三十九、检查变量是否等于一个字符串或另一个字符串

x = 'canada'

if x in ['canada', 'japan', 'germany', 'australia']:
    print("Yes")
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• 执行结果：

true
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四十、Python 字符串格式化固定宽度

num1 = 0.04154721841
num2 = 10.04154721841
num3 = 1002.04154721841

print "{0:<12.11g}".format(num1)[:12]
print "{0:<12.11g}".format(num2)[:12]
print "{0:<12.11g}".format(num3)[:12]
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• 执行结果：

100.041549
0.04159874
12.8878877
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四十一、在 Python 中查找字符串中字符的所有位置

test = 'canada#japan#uae'
c = '#'
print([pos for pos, char in enumerate(test) if char == c])
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• 执行结果：

[6, 12]
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四十二、在 Python 中从左右修剪指定数量的空格

def trim(text, num_of_leading, num_of_trailing):
    text = list(text)
    for i in range(num_of_leading):
        if text[i] == " ":
            text[i] = ""
        else:
            break

    for i in range(1, num_of_trailing+1):
        if text[-i] == " ":
            text[-i] = ""
        else:
            break
    return ''.join(text)

txt1 = "   Candada     "
print(trim(txt1, 1, 1))
print(trim(txt1, 2, 3))
print(trim(txt1, 6, 8))
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• 执行结果：

  Candada    
 Candada  
Candada
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四十三、在 Python 中按字符串中字符的位置拆分字符串

str = 'canadajapan'
splitat = 6
l, r = str[:splitat], str[splitat:]
print(l)
print(r)
1
2
3
4
5

• 执行结果：

canada
japan
1
2

四十四、将 Python 字符串中的第一个和最后一个字母大写

string = "canada"

result = string[0:1].upper() + string[1:-1].lower() + string[-1:].upper()
print(result)
1
2
3
4

• 执行结果：

CanadA
1

四十五、检查字符串是否以 Python 中的给定字符串或字符结尾

txt = "Canada is a great country"
x = txt.endswith("country")
print(x)
1
2
3

• 执行结果：

True
1

四十六、如何在 Python 中比较两个字符串

str1 = "Canada"
str2 = "Canada"
print(str1 is str2)  # True
print(str1 == str2)  # True
 
string1 = ''.join(['Ca', 'na', 'da'])
string2 = ''.join(['Can', 'ada'])
print(string1 is string2)  # False
print(string1 == string2)  # True
1
2
3
4
5
6
7
8
9

• 执行结果：

True
True
False
True
1
2
3
4

四十七、在 Python 中将整数格式化为带有前导零的字符串

x = 4
x = str(x).zfill(5)
print(x)
1
2
3

• 执行结果：

00004
1

四十八、在 Python 中替换字符串的多个子字符串

s = "The quick brown fox jumps over the lazy dog"
for r in (("brown", "red"), ("lazy", "quick")):
    s = s.replace(*r)

print(s)
1
2
3
4
5

• 执行结果：

The quick red fox jumps over the quick dog
1

四十九、Python 字符串替换字符

s = "The quick brown fox jumps over the lazy dog"
for r in (("brown", "red"), ("lazy", "quick")):
    s = s.replace(*r)

print(s)
1
2
3
4
5

• 执行结果：

The quick red fox jumps over the quick dog
1

五十、在 Python 中查找字符串中所有出现的单词的所有索引

import re

sentence = 'this is a sentence this this'
word = 'this'

for match in re.finditer(word, sentence):
    print(match.start(), match.end())
1
2
3
4
5
6
7

• 执行结果：

0 4
19 23
24 28
1
2
3

五十一、在 Python 中将字符串中每个单词的首字母大写

import string

x = "they're bill's friends from the UK"
x = string.capwords(x)
print(x)

x = x.title()
print(x)
1
2
3
4
5
6
7
8

• 执行结果：

They're Bill's Friends From The Uk
They'Re Bill'S Friends From The Uk
1
2

五十二、仅在 Python 中的双引号后拆分字符串

s = '"Canada", "Japan", "Germany", "Russia"'
l = ['"{}"'.format(s) for s in s.split('"') if s not in ('', ', ')]

for item in l:
    print(item)
1
2
3
4
5

• 执行结果：

"Canada"
"Japan"
"Germany"
"Russia"
1
2
3
4

五十三、在 Python 中以字节为单位获取字符串的大小

string1 = "Canada"
print(len(string1.encode('utf-16')))
1
2

• 执行结果：

10
1

五十四、在 Python 中比较字符串中的字符

myString = 'AAABBB'
for idx, char in enumerate(myString, ):
    if idx + 1 == len(myString):
        break
    if char == myString[idx + 1]:
        print(idx, char, myString[idx + 1])
1
2
3
4
5
6

• 执行结果：

0 A A
1 A A
3 B B
4 B B
1
2
3
4

五十五、在 Python 中的括号和字符串之间添加空格

import re

test = "example(test)"
test2 = "example(test)example"
test3 = "(test)example"
test4 = "example (test) example"

for i in [test, test2, test3, test4]:
    print(re.sub(r"[^\S]?(\(.*?\))[^\S]?", r" \1 ", i).strip())
1
2
3
4
5
6
7
8
9

• 执行结果：

example (test)
example (test) example
(test) example
example (test) example
1
2
3
4

五十六、在 Python 中删除开头和结尾空格

s = '   China   '
print(s.strip())
1
2

• 执行结果：

China
1

五十七、在 Python 中拆分字符串以获得第一个值

s = 'canada-japan-australia'
l = s.split('-')[0]
print(l)

string = 'canada-japan-australia'
print(string[:string.index('-')])
1
2
3
4
5
6

• 执行结果：

canada
canada
1
2

五十八、在 Python 中检查字符串是大写、小写还是混合大小写

words = ['The', 'quick', 'BROWN', 'Fox',
         'jumped', 'OVER', 'the', 'Lazy', 'DOG']
print([word for word in words if word.islower()])
print([word for word in words if word.isupper()])
print([word for word in words if not word.islower() and not word.isupper()])
1
2
3
4
5

• 执行结果：

['quick', 'jumped', 'the']
['BROWN', 'OVER', 'DOG']
['The', 'Fox', 'Lazy']
1
2
3

五十九、Python 计数字符串出现在给定字符串中

txt = "I love China, China is one of the most impressive countries in the world. China is a great country."
x = txt.count("China")
print(x)
1
2
3

• 执行结果：

3
1

六十、在 Python3 中用前导零填充字符串

hour = 4
minute = 3

print("{:0>2}:{:0>2}".format(hour, minute))
print("{:0>3}:{:0>5}".format(hour, minute))
print("{:0<3}:{:0<5}".format(hour, minute))
print("{:$<3}:{:#<5}".format(hour, minute))
1
2
3
4
5
6
7

• 执行结果：

04:03
004:00003
400:30000
4$$:3####
1
2
3
4

六十一、在 Python 中检查两个字符串是否包含相同的字母和数字

from string import ascii_letters, digits

def compare_alphanumeric(first, second):
    for character in first:
        if character in ascii_letters + digits and character not in second:
            return False
    return True

str1 = 'ABCD'
str2 = 'ACDB'
print(compare_alphanumeric(str1, str2))

str1 = 'A45BCD'
str2 = 'ACD59894B'
print(compare_alphanumeric(str1, str2))

str1 = 'A45BCD'
str2 = 'XYZ9887'
print(compare_alphanumeric(str1, str2))
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19

• 执行结果：

True
True
False
1
2
3

六十二、在 Python 中的字符串中的字符之间添加空格的有效方法

s = "ABCDEF"

print(" ".join(s))
print("-".join(s))
print(s.replace("", " ")[1: -1])
1
2
3
4
5

• 执行结果：

A B C D E F
A-B-C-D-E-F
A B C D E F
1
2
3

六十三、在 Python 中查找字符串中最后一次出现的子字符串的索引

s = 'What is China famous for?'

print(s.find('f'))
print(s.index('f'))
print(s.rindex('f'))
print(s.rfind('f'))
1
2
3
4
5
6

• 执行结果：

14
14
21
21
1
2
3
4

六十四、在 Python 中将字符串大写

x = 'China'
x = x.capitalize()
 
print(x)
1
2
3
4

• 执行结果：

China
1

六十五、拆分非字母数字并在 Python 中保留分隔符

import re

s = "65&Can-Jap#Ind^UK"
l = re.split('([^a-zA-Z0-9])', s)
print(l)
1
2
3
4
5

• 执行结果：

['65', '&', 'Can', '-', 'Jap', '#', 'Ind', '^', 'UK']
1

六十六、计算 Python 中字符串中大写和小写字符的数量

string = "asdfHRbySFss"

uppers = [l for l in string if l.isupper()]
print(len(uppers))

lowers = [l for l in string if l.islower()]
print(len(lowers))
1
2
3
4
5
6
7

• 执行结果：

4
8
1
2

六十七、在 Python 中将字符串与枚举进行比较

from enum import Enum, auto

class Signal(Enum):
     red = auto()
     green = auto()
     orange = auto()

     def equals(self, string):
          return self.name == string

brain_detected_colour = "red"
print(Signal.red.equals(brain_detected_colour))

brain_detected_colour = "pink"
print(Signal.red.equals(brain_detected_colour))
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15

• 执行结果：

True
False
1
2

六十八、Python 中的段落格式

import textwrap

hamlet = '''\
Lorum ipsum is the traditional Latin placeholder text, used when a designer needs a chunk of text for dummying up a layout.
Journo Ipsum is like that, only using some of the most common catchphrases, buzzwords, and bon mots of the future-of-news crowd.
Hit reload for a new batch. For entertainment purposes only.'''

wrapper = textwrap.TextWrapper(initial_indent='\t' * 1,
                               subsequent_indent='\t' * 2,
                               width=40)

for para in hamlet.splitlines():
    print(wrapper.fill(para))
1
2
3
4
5
6
7
8
9
10
11
12
13

• 执行结果：

	Lorum ipsum is the traditional Latin
		placeholder text, used when a designer
		needs a chunk of text for dummying up
		a layout.
	Journo Ipsum is like that, only using
		some of the most common catchphrases,
		buzzwords, and bon mots of the future-
		of-news crowd.
	Hit reload for a new batch. For
		entertainment purposes only.
1
2
3
4
5
6
7
8
9
10

六十九、从 Python 中的某个索引替换字符

def nth_replace(str,search,repl,index):
    split = str.split(search,index+1)
    if len(split)<=index+1:
        return str
    return search.join(split[:-1])+repl+split[-1]

str1 = "caars caars caars"
str2 = nth_replace(str1, 'aa', 'a', 1)

print(str2)
1
2
3
4
5
6
7
8
9
10

• 执行结果：

caars cars caars
1

七十、如何连接 str 和 int 对象

i = 123
a = "foobar"
s = a + str(i)
print(s)
1
2
3
4

• 执行结果：

foobar123
1

七十一、仅在 Python 中将字符串拆分为两部分

s = 'canada japan australia'
l = s.split(' ', 1)
print(l)
1
2
3

• 执行结果：

['canada', 'japan australia']
1

七十二、将大写字符串转换为句子大小写

text = ['CANADA', 'JAPAN']

text = [txt.capitalize() for txt in text]
print(text)
1
2
3
4

• 执行结果：

['Canada', 'Japan']
1

七十三、在标点符号上拆分字符串

string = 'a,b,c d!e.f\ncanada\tjapan&germany'
identifiers = '!"#$%&\'()*+,-./:;<=>?@[\\]^_`{|}~\n\t '

listitems = "".join((' ' if c in identifiers else c for c in string)).split()

for item in listitems:
    print(item)
1
2
3
4
5
6
7

• 执行结果：

a
b
c
d
e
f
canada
japan
germany
1
2
3
4
5
6
7
8
9

七十四、在 Python 中比较字符串

str1 = "Canada"
str2 = "Canada"
print(str1 is str2)  # True
print(str1 == str2)  # True
 
string1 = ''.join(['Ca', 'na', 'da'])
string2 = ''.join(['Can', 'ada'])
print(string1 is string2)  # False
print(string1 == string2)  # True
1
2
3
4
5
6
7
8
9

• 执行结果：

True
True
False
True
1
2
3
4

七十五、用零填充数字字符串

num = 123
print('{:<08d}'.format(num))
print('{:>08d}'.format(num))

string = '123'
print(string.ljust(8, '0'))
print(string.rjust(8, '0'))

print(string[::-1].zfill(8)[::-1])
1
2
3
4
5
6
7
8
9

• 执行结果：

12300000
00000123
12300000
00000123
12300000
1
2
3
4
5

七十六、找到两个字符串之间的差异位置

def dif(a, b):
    return [i for i in range(len(a)) if a[i] != b[i]]

print(dif('stackoverflow', 'stacklavaflow'))
1
2
3
4

• 执行结果：

[5, 6, 7, 8]
1

七十七、Python 填充字符串到固定长度

number = 4

print(f'{number:05d}')  # (since Python 3.6), or
print('{:05d}'.format(number))  # or

print('{0:05d}'.format(number))
print('{n:05d}'.format(n=number))  # or (explicit `n` keyword arg. selection)
print(format(number, '05d'))
1
2
3
4
5
6
7
8

• 执行结果：

00004
00004
00004
00004
00004
00004
1
2
3
4
5
6

七十八、Python 中的字符串查找示例

import re

text = 'This is sample text to test if this pythonic '\
       'program can serve as an indexing platform for '\
       'finding words in a paragraph. It can give '\
       'values as to where the word is located with the '\
       'different examples as stated'

find_the_word = re.finditer('as', text)

for match in find_the_word:
    print('start {}, end {}, search string \'{}\''.
          format(match.start(), match.end(), match.group()))
1
2
3
4
5
6
7
8
9
10
11
12
13

• 执行结果：

start 63, end 65, search string 'as'
start 140, end 142, search string 'as'
start 200, end 202, search string 'as'
1
2
3

七十九、删除字符串中的开头零和结尾零

list_num = ['000231512-n', '1209123100000-n00000',
             'alphanumeric0000', '000alphanumeric']
 
print([item.strip('0') for item in list_num])   # Remove leading + trailing '0'
print([item.lstrip('0') for item in list_num])  # Remove leading '0'
print([item.rstrip('0') for item in list_num])  # Remove trailing '0'
1
2
3
4
5
6

• 执行结果：

['231512-n', '1209123100000-n', 'alphanumeric', 'alphanumeric']
['231512-n', '1209123100000-n00000', 'alphanumeric0000', 'alphanumeric']
['000231512-n', '1209123100000-n', 'alphanumeric', '000alphanumeric']
1
2
3

八十、Python 在换行符上拆分

s = 'line 1\nline 2\nline without newline'
l = s.splitlines(True)

print(l)
1
2
3
4

• 执行结果：

['line 1\n', 'line 2\n', 'line without newline']
1

八十一、将字符串中的每个第二个字母大写

s = 'canada'
s = "".join([x.upper() if i % 2 != 0 else x for i, x in enumerate(s)])

print(s)
1
2
3
4

八十二、在 Python 中查找一个月的最后一个营业日或工作日

import calendar

def last_business_day_in_month(year: int, month: int) -> int:
    return max(calendar.monthcalendar(year, month)[-1:][0][:5])

print(last_business_day_in_month(2021, 1))
print(last_business_day_in_month(2021, 2))
print(last_business_day_in_month(2021, 3))
print(last_business_day_in_month(2021, 4))
print(last_business_day_in_month(2021, 5))
1
2
3
4
5
6
7
8
9
10

• 执行结果：

29
26
31
30
31
1
2
3
4
5

八十三、比较两个字符串中的单个字符

def compare_strings(a, b):
    result = True
    if len(a) != len(b):
        print('string lengths do not match!')
    for i, (x, y) in enumerate(zip(a, b)):
        if x != y:
            print(f'char miss-match {x, y} in element {i}')
            result = False
    if result:
        print('strings match!')
    return result
print(compare_strings("canada", "japan"))
1
2
3
4
5
6
7
8
9
10
11
12

• 执行结果：

string lengths do not match!
char miss-match ('c', 'j') in element 0
char miss-match ('n', 'p') in element 2
char miss-match ('d', 'n') in element 4
False
1
2
3
4
5

八十四、在 Python 中多次显示字符串

print('canada' * 3)
print(*3 * ('canada',), sep='-')
1
2

• 执行结果：

canadacanadacanada
canada-canada-canada
1
2

八十五、Python 从头开始替换字符串

def nth_replace(s, old, new, occurrence):
    li = s.rsplit(old, occurrence)
    return new.join(li)

str1 = "caars caars caars caars caars"
str2 = nth_replace(str1, 'aa', 'a', 1)
print(str2)

str2 = nth_replace(str1, 'aa', 'a', 2)
print(str2)

str2 = nth_replace(str1, 'aa', 'a', 3)
print(str2)
1
2
3
4
5
6
7
8
9
10
11
12
13

• 执行结果：

caars caars caars caars cars
caars caars caars cars cars
caars caars cars cars cars
1
2
3

八十六、在 Python 中连接字符串和变量值

year = '2020'

print('test' + str(year))
print('test' + year.__str__())
1
2
3
4

• 执行结果：

test2020
test2020
1
2

八十七、在每个下划线处拆分字符串并在第 N 个位置后停止

s = 'canada_japan_australia_us_uk'
l = s.split('_', 0)
print(l)

l = s.split('_', 1)
print(l)

l = s.split('_', 2)
print(l)
1
2
3
4
5
6
7
8
9

• 执行结果：

['canada_japan_australia_us_uk']
['canada', 'japan_australia_us_uk']
['canada', 'japan', 'australia_us_uk']
1
2
3

八十八、Python 中列表中第一个单词的首字母大写

text = ['johnny rotten', 'eddie vedder', 'kurt kobain',
           'chris cornell', 'micheal phillip jagger']

text = [txt.capitalize() for txt in text]
print(text)
1
2
3
4
5

• 执行结果：

['Johnny rotten', 'Eddie vedder', 'Kurt kobain', 'Chris cornell', 'Micheal phillip jagger']
1

八十九、如何在 Python 字符串中找到第一次出现的子字符串

test = 'Position of a character'
print(test.find('of'))
print(test.find('a'))
1
2
3

• 执行结果：

9
12
1
2

九十、不同长度的 Python 填充字符串

data = [1148, 39, 365, 6, 56524]

for element in data:
    print("{:>5}".format(element))
1
2
3
4

• 执行结果：

1148
   39
  365
    6
56524
1
2
3
4
5

九十一、Python 比较两个字符串保留一端的差异

def after(s1, s2):
    index = s1.find(s2)
    if index != -1 and index + len(s2) < len(s1):
        return s1[index + len(s2):]
    else:
        return None

s1 = "canada"
s2 = "can"

print(after(s1, s2))
1
2
3
4
5
6
7
8
9
10
11

• 执行结果：

ada
1

九十二、如何用 Python 中的一个字符替换字符串中的所有字符

test = 'canada'
print('$' * len(test))
1
2

• 执行结果：

$$$$$$
1

九十三、在字符串中查找子字符串并在 Python 中返回子字符串的索引

def find_str(s, char):
    index = 0

    if char in s:
        c = char[0]
        for ch in s:
            if ch == c:
                if s[index:index + len(char)] == char:
                    return index
            index += 1
    return -1
    
print(find_str("India Canada Japan", "Canada"))
print(find_str("India Canada Japan", "cana"))
print(find_str("India Canada Japan", "Uae"))
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15

• 执行结果：

6
-1
-1
1
2
3

九十四、从 Python 中的字符串中修剪特定的开头和结尾字符

number = '+91 874854778'

print(number.strip('+'))
print(number.lstrip('+91'))
1
2
3
4

• 执行结果：

91 874854778
 874854778
1
2

九十五、在 Python 中按长度将字符串拆分为字符串

string = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"

x = 3
res = [string[y - x:y] for y in range(x, len(string) + x, x)]
print(res)
1
2
3
4
5

• 执行结果：

['ABC', 'DEF', 'GHI', 'JKL', 'MNO', 'PQR', 'STU', 'VWX', 'YZ']
1

九十六、如何在 Python 中将字符串的第三个字母大写

s = "xxxyyyzzz"

# convert to list
a = list(s)

# change every third letter in place with a list comprehension
a[2::3] = [x.upper() for x in a[2::3]]

# back to a string
s = ''.join(a)

print(s)
1
2
3
4
5
6
7
8
9
10
11
12

• 执行结果：

xxXyyYzzZ
1

九十七、将制表符大小设置为指定的空格数

txt = "Canada\tis\ta\tgreat\tcountry"

print(txt)
print(txt.expandtabs())
print(txt.expandtabs(2))
print(txt.expandtabs(4))
print(txt.expandtabs(10))
1
2
3
4
5
6
7

• 执行结果：

Canada	is	a	great	country
Canada  is      a       great   country
Canada  is  a great country
Canada  is  a   great   country
Canada    is        a         great     country
1
2
3
4
5

九十八、将两个字符串与某些字符进行比较

str1 = "Can"
str2 = "Canada"
print(str1 in str2)
print(str1.startswith(str2))
print(str2.startswith(str1))

print(str1.endswith(str2))

str3 = "CAN"
print(str3 in str2)
1
2
3
4
5
6
7
8
9
10

• 执行结果：

True
False
True
False
False
1
2
3
4
5

九十九、字符串格式化填充负数

n = [-2, -8, 1, -10, 40]

num = ["{1:0{0}d}".format(2 if x >= 0 else 3, x) for x in n]
print(num)
1
2
3
4

• 执行结果：

n = [-2, -8, 1, -10, 40]

num = ["{1:0{0}d}".format(2 if x >= 0 else 3, x) for x in n]
print(num)
1
2
3
4

一百、单独替换字符串中的第一个字符

str1 = "caars caars caars"
str2 = str1.replace('aa', 'a', 1)

print(str2)
1
2
3
4

• 执行结果：

cars caars caars
1

一百零一、连接固定字符串和变量

variable = 'Hello'
print('This is the Test File ' + variable)

variable = '10'
print('This is the Test File ' + str(variable))
1
2
3
4
5

• 执行结果：

This is the Test File Hello
This is the Test File 10
1
2

一百零二、将字符串拆分为多个字符串

s = 'str1, str2, str3, str4'
l = s.split(', ')
 
print(l)
1
2
3
4

• 执行结果：

['str1', 'str2', 'str3', 'str4']
1

一百零三、在 Python 中将字符串大写

x = "canada japan australia"

x = x[:1].upper() + x[1:]
print(x)

x= x.capitalize()
print(x)

x= x.title()
print(x)
1
2
3
4
5
6
7
8
9
10

• 执行结果：

Canada japan australia
Canada japan australia
Canada Japan Australia
1
2
3

一百零四、将字节字符串拆分为单独的字节

data = b'\x00\x00\x00\x00\x00\x00'

info = [data[i:i + 2] for i in range(0, len(data), 2)]
print(info)
1
2
3
4

• 执行结果：

[b'\x00\x00', b'\x00\x00', b'\x00\x00']
1

一百零五、用空格填写 Python 字符串

string = 'Hi'.ljust(10)
print(string)

string = 'Hi'.rjust(10)
print(string)

string = '{0: ^20}'.format('Hi')
print(string)

string = '{message: >16}'.format(message='Hi')
print(string)

string = '{message: <16}'.format(message='Hi')
print(string)

string = '{message: <{width}}'.format(message='Hi', width=20)
print(string)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17

• 执行结果：

Hi        
        Hi
         Hi         
              Hi
Hi              
Hi
1
2
3
4
5
6

一百零六、比较两个字符串并检查它们共有多少个字符

from collections import Counter

def shared_chars(s1, s2):
    return sum((Counter(s1) & Counter(s2)).values())

print(shared_chars('car', 'carts'))
1
2
3
4
5
6

• 执行结果：

3
1

一百零七、在 Python 中的数字和字符串之间添加空格

import re

s = "ABC24.00XYZ58.28PQR"
s = re.sub("[A-Za-z]+", lambda group: " " + group[0] + " ", s)
print(s.strip())
1
2
3
4
5

• 执行结果：

ABC 24.00 XYZ 58.28 PQR
1

一百零八、如何在 Python 中去除空格

s = '   canada  '
print(s.rstrip())  # For whitespace on the right side use rstrip.
print(s.lstrip())  # For whitespace on the left side lstrip.
print(s.strip())  # For whitespace from both side.
 
 
s = ' \t  canada  '
print(s.strip('\t'))  # This will strip any space, \t, \n, or \r characters from the left-hand side, right-hand side, or both sides of the string.
1
2
3
4
5
6
7
8

• 执行结果：

   canada
canada  
canada
          canada
1
2
3
4

一百零九、字符串中最后一次出现的分隔符处拆分字符串

s = 'canada-japan-australia-uae-india'
l = s.rsplit('-', 1)[1]
print(l)
1
2
3

• 执行结果：

india
1

一百一十、在 Python 中将字符串的最后一个字母大写

string = "canada"

result = string[:-1] + string[-1].upper()
print(result)

result = string[::-1].title()[::-1]
print(result)
1
2
3
4
5
6
7

• 执行结果：

canadA
canadA
1
2

一百一十一、使用指定字符居中对齐字符串

txt = "canada"
x = txt.center(20)
print(x)
1
2
3

• 执行结果：

       canada
1

一百一十二、格式字符串中动态计算的零填充

x = 4
w = 5
print('{number:0{width}d}'.format(width=w, number=x))
1
2
3

• 执行结果：

00004
1

一百一十三、在 Python 中使用 string.replace()

a = "This is the island of istanbul"
print (a.replace("is" , "was", 1))
print (a.replace("is" , "was", 2))
print (a.replace("is" , "was"))
1
2
3
4

• 执行结果：

Thwas is the island of istanbul
Thwas was the island of istanbul
Thwas was the wasland of wastanbul
1
2
3

一百一十四、在 Python 中获取字符的位置

test = 'Position of a character'
print(test.find('of'))
print(test.find('a'))
1
2
3

• 执行结果：

9
12
1
2

一百一十五、Python 字符串替换多次出现

s = "The quick brown fox jumps over the lazy dog"
for r in (("brown", "red"), ("lazy", "quick")):
    s = s.replace(*r)

print(s)
1
2
3
4
5

• 执行结果：

The quick red fox jumps over the quick dog
1

一百一十六、在索引后找到第一次出现的字符

string = 'This + is + a + string'
x = string.find('+', 4)
print(x)

x = string.find('+', 10)
print(x)
1
2
3
4
5
6

• 执行结果：

5
10
1
2

一百一十七、在 Python 中将字符串更改为大写

x = 'canada'
x = x.upper()

print(x)
1
2
3
4

• 执行结果：

CANADA
1

一百一十八、在 Python 中拆分具有多个分隔符的字符串

import re

l = re.split(r'[$-]+', 'canada$-india$-japan$-uae')
print(l)
1
2
3
4

• 执行结果：

['canada', 'india', 'japan', 'uae']
1

一百一十九、在 Python 中获取字符串的大小

string1 = "Canada"
print(len(string1))

string2 = "  Canada"
print(len(string2))

string3 = "Canada  "
print(len(string3))
1
2
3
4
5
6
7
8

• 执行结果：

6
8
8
1
2
3

一百二十、Python 中的字符串比较 is vs ==

x = 'canada'
y = ''.join(['ca', 'na', 'da'])
print(x == y)
print(x is y)
 
x = [1, 2, 3]
y = [1, 2, 3]
print(x == y)
print(x is y)
 
z = y
print(z is y)
1
2
3
4
5
6
7
8
9
10
11
12

• 执行结果：

True
False
True
False
True
1
2
3
4
5

一百二十一、每当数字与非数字相邻时，Python 正则表达式都会添加空格

import re

text = ['123', 'abc', '4x5x6', '7.2volt', '60BTU',
        '20v', '4*5', '24in', 'google.com-1.2', '1.2.3']

pattern = r'(-?[0-9]+\.?[0-9]*)'
for data in text:
    print(repr(data), repr(
        ' '.join(segment for segment in re.split(pattern, data) if segment)))
1
2
3
4
5
6
7
8
9

• 执行结果：

'123' '123'
'abc' 'abc'
'4x5x6' '4 x 5 x 6'
'7.2volt' '7.2 volt'
'60BTU' '60 BTU'
'20v' '20 v'
'4*5' '4 * 5'
'24in' '24 in'
'google.com-1.2' 'google.com -1.2'
'1.2.3' '1.2 . 3'
1
2
3
4
5
6
7
8
9
10

一百二十二、在 Python 中仅按第一个空格拆分字符串

s = 'canada japan australia'
l = s.split(' ', 1)
print(l)
1
2
3

• 执行结果：

['canada', 'japan australia']
1

一百二十三、在 Python 中将字符串中的一些小写字母更改为大写

indices = set([0, 7, 14, 18])

s = "i love China"
print("".join(c.upper() if i in indices else c for i, c in enumerate(s)))
1
2
3
4

• 执行结果：

I love China
1

一百二十四、将字符串拆分为具有多个单词边界分隔符的单词

import re

thestring = "a,b,c d!e.f\ncanada\tjapan&germany"
listitems = re.findall('\w+', thestring)

for item in listitems:
    print(item)
1
2
3
4
5
6
7

• 执行结果：

a
b
c
d
e
f
canada
japan
germany
1
2
3
4
5
6
7
8
9

一百二十五、检查一个字符串在 Python 中是否具有相同的字符

str1 = 'caars'
str2 = 'rats'
str3 = 'racs'

print(set(str1)==set(str2))
print(set(str1)==set(str3))
1
2
3
4
5
6

• 执行结果：

False
True
1
2

一百二十六、在多个分隔符或指定字符上拆分字符串

import re
 
string_test = "Ethnic (279), Responses (3), 2016 Census - 25% Sample"
print(re.findall(r"[\w']+", string_test))
 
def split_by_char(s, seps):
    res = [s]
    for sep in seps:
        s, res = res, []
        for seq in s:
            res += seq.split(sep)
    return res
 
print(split_by_char(string_test, [' ', '(', ')', ',']))
1
2
3
4
5
6
7
8
9
10
11
12
13
14

• 执行结果：

['Ethnic', '279', 'Responses', '3', '2016', 'Census', '25', 'Sample']
['Ethnic', '', '279', '', '', 'Responses', '', '3', '', '', '2016', 'Census', '-', '25%', 'Sample']
1
2

一百二十七、将一个字符串附加到另一个字符串

# Example 1
str1 = "Can"
str2 = "ada"
str3 = str1 + str2
print(str3)
 
# Example 2
str4 = 'Ca'
str4 += 'na'
str4 += 'da'
print(str4)
 
# Example 3
join_str = "".join((str1, str2))
print(join_str)
 
# Example 4
str_add = str1.__add__(str2)
print(str_add)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19

• 执行结果：

Canada
Canada
Canada
Canada
1
2
3
4

一百二十八、在 Python 中遍历字符串

# Example 1
test_str = "Canada"
for i, c in enumerate(test_str):
        print(i, c)
 
print("------------------------")
 
# Example 2
indx = 0
while indx < len(test_str):
        print(indx, test_str[indx])
        indx += 1
 
print("------------------------")
# Example 3
for char in test_str:
        print(char)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17

• 执行结果：

0 C
1 a
2 n
.......
d
a
1
2
3
4
5
6

一百二十九、从 Python 中的字符串中去除标点符号

import string
import re
 
# Example 1
s = "Ethnic (279), Responses (3), 2016 Census - 25% Sample"
out = re.sub(r'[^\w\s]', '', s)
print(out)
 
# Example 2
s = "Ethnic (279), Responses (3), 2016 Census - 25% Sample"
for p in string.punctuation:
        s = s.replace(p, "")
print(s)
 
# Example 3
s = "Ethnic (279), Responses (3), 2016 Census - 25% Sample"
out = re.sub('[%s]' % re.escape(string.punctuation), '', s)
print(out)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18

• 执行结果：

Ethnic 279 Responses 3 2016 Census  25 Sample
Ethnic 279 Responses 3 2016 Census  25 Sample
Ethnic 279 Responses 3 2016 Census  25 Sample
1
2
3

一百三十、将列表转换为字符串

list_exp = ['Ca', 'na', 'da']
print(type(list_exp))
 
# Example 1
str_exp1 = ''.join(list_exp)
print(type(str_exp1))
print(str_exp1)
 
# Example 2
str_exp2 = ''.join(str(e) for e in list_exp)
print(type(str_exp2))
print(str_exp2)
 
# Example 3
str_exp3 = ''.join(map(str, list_exp))
print(type(str_exp2))
print(str_exp2)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17

• 执行结果：

class 'list'
class 'str'
Canada
class 'str'
Canada
class 'str'
Canada
1
2
3
4
5
6
7

一百三十一、将 JSON 转换为字符串

import json
 
 
# list with dict a simple Json format
json_exp = \
    [{"id": "12", "name": "Mark"}, {"id": "13", "name": "Rock", "date": None}]
print(type(json_exp))
 
str_conv = json.dumps(json_exp)  # string
print(type(str_conv))
print(str_conv)
1
2
3
4
5
6
7
8
9
10
11

• 执行结果：

class 'list'

class 'str'

[{"id": "12", "name": "Mark"}, {"id": "13", "name": "Rock", "date": null}]
1
2
3
4
5

一百三十二、对字符串列表进行排序

# Example 1
str_list = ["Japan", "Canada", "Australia"]
print(str_list)
str_list.sort()
print(str_list)
 
# Example 2
str_list = ["Japan", "Canada", "Australia"]
for x in sorted(str_list):
    print(x)
 
# Example 3
str_var = "Canada"
strlist = sorted(str_var)
print(strlist)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15

• 执行结果：

['Japan', 'Canada', 'Australia']
['Australia', 'Canada', 'Japan']
Australia
Canada
Japan
['C', 'a', 'a', 'a', 'd', 'n']
1
2
3
4
5
6

一百三十三、在 Python 中检查字符串是否以 XXXX 开头

import re
 
 
exp_str = "Python Programming"
 
# Example 1
if re.match(r'^Python', exp_str):
    print(True)
else:
    print(False)
 
# Example 2
result = exp_str.startswith("Python")
print(result)
1
2
3
4
5
6
7
8
9
10
11
12
13
14

• 执行结果：

True
True
1
2

一百三十四、在 Python 中将两个字符串网格或交错在一起的不同方法

str1 = "AAAA"
str2 = "BBBBBBBBB"
 
# Example 1
mesh = "".join(i + j for i, j in zip(str1, str2))
print("Example 1:", mesh)
 
# Example 2
min_len = min(len(str1), len(str2))
mesh = [''] * min_len * 2
mesh[::2] = str1[:min_len]
mesh[1::2] = str2[:min_len]
print("Example 2:", ''.join(mesh))
 
# Example 3
mesh = ''.join(''.join(item) for item in zip(str1, str2))
print("Example 3:", mesh)
 
# Example 4
min_len = min(len(str1), len(str2))
mesh = [''] * min_len * 2
mesh[::2] = str1[:min_len]
mesh[1::2] = str2[:min_len]
mesh += str1[min_len:] + str2[min_len:]
print("Example 4:", ''.join(mesh))
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25

• 执行结果：

Example 1: ABABABAB
Example 2: ABABABAB
Example 3: ABABABAB
Example 4: ABABABABBBBBB
1
2
3
4