标签：arc replace 区分大小写 style jquery $$ 内容 javascrip blog
1.定义正则表达式
2.匹配正则表达式
非全局模式，不分组
var pattern = /^Java\w*/m; var text = "JavaScript is more fun than JavaEE or JavaBeans!"; pattern.exec(text) pattern.exec(text) pattern.exec(text)
执行结果：
["JavaScript"] ["JavaScript"] ["JavaScript"]
非全局模式，分组
var pattern = /^Java(\w*)/m; var text = "JavaScript is more fun than \nJavaEE or JavaBeans!"; pattern.exec(text) pattern.exec(text) pattern.exec(text)
执行结果：
["JavaScript", "Script"] ["JavaScript", "Script"] ["JavaScript", "Script"]
全局模式，不分组
var pattern = /^Java\w*/gm var text = "JavaScript is more fun than JavaEE or JavaBeans!"; pattern.exec(text) pattern.exec(text) pattern.exec(text) pattern.exec(text)
执行结果：
["JavaScript"] null ["JavaScript"] null
全局模式，分组
var pattern = /^Java(\w*)/gm; var text = "JavaScript is more fun than JavaEE or JavaBeans!"; pattern.exec(text) pattern.exec(text) pattern.exec(text) pattern.exec(text) 执行结果：
["JavaScript", "Script"] null ["JavaScript", "Script"] null
3.
obj.search(regexp) 获取索引位置，搜索整个字符串，返回匹配成功的第一个位置(g模式无效)
obj.match(regexp) 获取匹配内容，搜索整个字符串，获取找到第一个匹配内容，如果正则是g模式找到全部
obj.replace(regexp, replacement) 替换匹配替换，正则中有g则替换所有，否则只替换第一个匹配项，
$数字：匹配的第n个组内容；
$&：当前匹配的内容；
$`：位于匹配子串左侧的文本；
$‘：位于匹配子串右侧的文本
$$：直接量$符号
var text = "JavaScript is more fun than \nJavaEE or JavaBeans!"; text.match(/Java\w+/mg);
["JavaScript", "JavaEE", "JavaBeans"]
var text = "JavaScript is more fun than \nJavaEE or JavaBeans!"; text.replace(/Java\w+/mg,‘Python‘);
"Python is more fun than
Python or Python!"
var text = "JavaScript is 8 more fun than 7 JavaEE or 6 JavaBeans!"; text.replace(/\d+/gm,‘Python‘);
"JavaScript is Python more fun than Python JavaEE or Python JavaBeans!"
var text = "JavaScript is 8 more fun than 7 JavaEE or 6 JavaBeans!"; text.replace(/\d+/gm,‘Python$&‘);
"JavaScript is Python8 more fun than Python7 JavaEE or Python6 JavaBeans!"
var text = "JavaScript is more fun than JavaEE or JavaBeans!"; text.replace(/Java/,‘==Python==$\‘‘); "==Python==Script is more fun than JavaEE or JavaBeans!Script is more fun than JavaEE or JavaBeans!" text.replace(/Java/,‘==Python==$`‘); "==Python==Script is more fun than JavaEE or JavaBeans!"
标签：arc replace 区分大小写 style jquery $$ 内容 javascrip blog
原文地址：http://www.cnblogs.com/python-study/p/5984762.html
