Python文本的艺术字符串处理技巧掌握

text1 = 'Hello, World!'
text2 = "Python Programming"
text3 = '''This is a
multiline string.'''

greeting = "Hello"
name = "Alice"
message = greeting + ", " + name + "!"

stars = "*" * 10

text = "Python"
length = len(text)  # 返回值为 6

text = "Hello, World!"
upper_text = text.upper()  # "HELLO, WORLD!"
lower_text = text.lower()  # "hello, world!"

text = "  Python   "
clean_text = text.strip()  # "Python"

name = "Alice"
age = 30
message = "My name is %s and I am %d years old." % (name, age)

name = "Alice"
age = 30
message = f"My name is {name} and I am {age} years old."

text = "Python"
substring = text[2:4]  # "th"

sentence = "Hello, how are you?"
words = sentence.split()  # ["Hello,", "how", "are", "you?"]

# 统计单词频率
text = "This is a sample text. It contains some sample words."
word_count = {}
words = text.split()
for word in words:
    if word in word_count:
        word_count[word] += 1
    else:
        word_count[word] = 1

# 验证邮箱地址
import re
email = input("请输入邮箱地址：")
if re.match(r"[^@]+@[^@]+\.[^@]+", email):
    print("邮箱地址有效")
else:
    print("邮箱地址无效")