import re
# 將所有數(shù)字替換為"*"
text = "密碼: 123456, 驗證碼: 789"
result = re.sub(r"\d+", "*", text)
print(result)  # 輸出: 密碼: *, 驗證碼: *
# 限制替換次數(shù)（只替換前1個）
result = re.sub(r"\d+", "*", text, count=1)
print(result)  # 輸出: 密碼: *, 驗證碼: 789

import re
# 交換姓名格式：" lastName, firstName" → "firstName lastName"
text = "Bond, James; Doe, John"
pattern = r"(\w+), (\w+)"  # 分組1：姓氏，分組2：名字
result = re.sub(pattern, r"\2 \1", text)  # 用\2和\1交換順序
print(result)  # 輸出: James Bond; John Doe
# 格式化日期："MM/DD/YYYY" → "YYYY-MM-DD"
text = "今天是10/05/2023，昨天是10/04/2023"
pattern = r"(\d{2})/(\d{2})/(\d{4})"  # 分組1：月，分組2：日，分組3：年
result = re.sub(pattern, r"\3-\1-\2", text)
print(result)  # 輸出: 今天是2023-10-05，昨天是2023-10-04

import re
# 將數(shù)字乘以2（如"3"→"6"，"10"→"20"）
def double_num(match):
    num = int(match.group())  # 獲取匹配的數(shù)字
    return str(num * 2)
text = "單價: 5, 數(shù)量: 3, 總價: 15"
result = re.sub(r"\d+", double_num, text)
print(result)  # 輸出: 單價: 10, 數(shù)量: 6, 總價: 30
# 敏感信息脫敏：保留手機號前3位和后4位，中間用*代替
def mask_phone(match):
    phone = match.group()
    return phone[:3] + "****" + phone[-4:]
text = "聯(lián)系電話: 13812345678, 備用電話: 19987654321"
result = re.sub(r"1[3-9]\d{9}", mask_phone, text)
print(result)  # 輸出: 聯(lián)系電話: 138****5678, 備用電話: 199****4321

import re
# 將"apple"（不區(qū)分大小寫）替換為"banana"
text = "Apple, APPLE, apple"
result = re.sub(r"apple", "banana", text, flags=re.IGNORECASE)
print(result)  # 輸出: banana, banana, banana

import re
# 移除HTML標簽（如<a>、<div>等）
html = "<h1>標題</h1><p>內(nèi)容</p>"
result = re.sub(r"<.*?>", "", html)  # 匹配所有標簽并替換為空
print(result)  # 輸出: 標題內(nèi)容
# 移除字符串中的所有標點符號
text = "Hello, World! 這是一個示例：test."
result = re.sub(r"[^\w\s]", "", text)  # [^\w\s]匹配非單詞和非空白字符
print(result)  # 輸出: Hello World 這是一個示例 test