使用Python进行字符串查找与替换的方法详解

text = "Hello, world! Welcome to Python programming."
# 查找子字符串的位置
position = text.find("world")
print(f"Found 'world' at position: {position}")
 
# 替换子字符串
new_text = text.replace("Python", "Java")
print(new_text)

import re
 
pattern = r"\bworld\b"  # \b表示单词边界
matches = re.findall(pattern, text)
print(f"Words matching '{pattern}': {matches}")
 
# 分组捕获
pattern_with_group = r"(\w+)@(\w+\.\w+)"
email = "user@example.com"
match = re.search(pattern_with_group, email)
if match:
    username, domain = match.groups()
    print(f"Username: {username}, Domain: {domain}")

pip install fuzzywuzzy python-Levenshtein 

from fuzzywuzzy import fuzz
 
text_to_match = "pythoon"
guess = "Python"
# 比较相似度
similarity = fuzz.ratio(text_to_match, guess)
print(f"Similarity: {similarity}%")
 
# 最佳匹配
choices = ["Java", "Python", "Ruby"]
best_match = max(choices, key=lambda x: fuzz.token_sort_ratio(x, text_to_match))
print(f"Best Match: {best_match}")

filename = "largefile.txt"
 
with open(filename, 'r') as file:
    for line in file:
        if "keyword" in line:
            print(f"Found keyword in line: {line.strip()}")

import re
 
error_pattern = r"ERROR: (.*)"
 
def analyze_log(file_path):
    error_logs = []
    with open(file_path, 'r') as log_file:
        for line in log_file:
            match = re.search(error_pattern, line)
            if match:
                error_logs.append(match.group(1))
    return error_logs
 
# 假设日志文件名为"log.txt"
errors = analyze_log("log.txt")
for error in errors:
    print(f"Error: {error}")