RE(正则)和Xpath

	验证一个数字:	 					^\d$
	必须有一个数字，最少一位:			^\d+$
	只能出现数字，且位数为5-10位:	    ^\d{5,10}$
	注册者年龄 16岁以上，99岁以下:      ^[16-99]$
	只能输入英文字符和数字:				^[A-Za-z0-9]$
	验证qq号码：						^[0-9]{5,12}

import re
p = re.compile(r'\d+')
## 3,10 表示查找的范围
m = p.match("qwq1233qewsfsfrrgrsc",3,10)
print(m)
## match 可以输入参数；查到的结果只包含一个  表示第一次匹配成功的内容
-------------------------------------------------------------
结果：<_sre.SRE_Match object; span=(3, 7), match='1233'>
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
import re
# I表示忽略大小写
p = re.compile(r'([a-z]+) ([a-z]+)',re.I)
m = p.match('I am really love you')
print(m)
-----------------------------------------------------------------
结果：<_sre.SRE_Match object; span=(0, 4), match='I am'>

import re
p = re.compile(r'\d+')
m = p.findall("one1two2three34")   
a = p.search("one1two2three34")
print(a)
print(m)
---------------------------------------------------------------------------
结果：<_sre.SRE_Match object; span=(3, 4), match='1'>
 	 ['1', '2', '34']
+++++++++++++++++++++++++++++++++++++++++++++++++++++
#替换
import re
p = re.compile(r'(\w+) (\w+)')
s = "hello 123 wang 123 xiao 456 jing, i love you"
rst = p.sub(r'hello world',s)
print(rst)
---------------------------------------
结果：hello world hello world hello world jing, hello world you

import re
title = '<div>name</div><div>age</div>'
p1 = re.compile(r"<div>.*</div>")
p2 = re.compile(r'<div>.*?</div>')

r1 = p1.match(title)
r2 = p2.search(title)
print(r1.group())
print(r2.group())
-----------------------------------------
结果：<div>name</div><div>age</div>
	 <div>name</div>

import re

title = u'世界你好 hello moto'
p = re.compile(r'[\u4e00-\u9fa5]+')
rst = p.findall(title)
print(rst)
-----------------------------
结果：['世界你好']