import re
str = '123Aabc456Adef789Aghi'
# 匹配开头字符串,失败为None,成功有值,这个相当于正则中以^匹配开头字符串
result = re.match('abc', str)
print(result)
#上面另一种写法
pattern = re.compile(r'abc')
result = pattern.match(str)
print(result)
# 扫描整个字符串并返回第一个成功的匹配、
result = re.search(r'abc', str)
print(result)
# 正则替换
result = re.sub('\\d+', 'haha', str)
print(result)
# 匹配所有字符串
result = re.findall('A[a-z]+', str)
print(result)
# 匹配所有字符串
results = re.finditer('A[a-z]+', str)
for result in results:
print(result.group())
# 匹配子表达式
results = re.finditer('A([a-z]+)', str)
for result in results:
print(result.group(1))
# 正则分割
results = re.split('A[a-z]+', str)
print(results)