Python学习笔记第十八周

Posted 2020-09-24

目录：

　　一、JavaScript正则表达式

 

 

内容：

　　一、JavaScript正则表达式

　　　　1、test   

　　　　判断字符串是否符合规定的正则表达式

　　　　例子：

　　　　rep = /^\d+$/

　　　　rep.test(‘123‘)返回true

 

　　　　2、exec

　　　　获取匹配的数据，在匹配时，默认只能匹配到第一个即返回，且匹配值以数组形式存在

　　　　例子：分组匹配，会匹配两次，第一次匹配整体，第二次会将分组内容单独匹配出来

test = ‘JavaScript is more fun than Java or JavaBeans!‘
"JavaScript is more fun than Java or JavaBeans!"
var pattern = /\bJava\w*\b/
undefined
pattern.exec(test)
输出：["JavaScript", index: 0, input: "JavaScript is more fun than Java or JavaBeans!"]

var pattern = /\bJava(\w*)\b/
pattern.exec(test)
输出：(2) ["JavaScript", "Script", index: 0, input: "JavaScript is more fun than Java or JavaBeans!"]

　　例子2：全局匹配 在匹配模板后面加g

　　

test = ‘JavaScript is more fun than Java or JavaBeans!‘
"JavaScript is more fun than Java or JavaBeans!"
var pattern = /\bJava\w*\b/g
undefined
pattern.exec(test)
["JavaScript", index: 0, input: "JavaScript is more fun than Java or JavaBeans!"]
pattern.exec(test)
["Java", index: 28, input: "JavaScript is more fun than Java or JavaBeans!"]
pattern.exec(test)
["JavaBeans", index: 36, input: "JavaScript is more fun than Java or JavaBeans!"]

没有加分组的情况

var pattern = /\bJava(\w*)\b/g
undefined
test = ‘JavaScript is more fun than Java or JavaBeans!‘
"JavaScript is more fun than Java or JavaBeans!"
pattern.exec(test)
(2) ["JavaScript", "Script", index: 0, input: "JavaScript is more fun than Java or JavaBeans!"]
pattern.exec(test)
(2) ["Java", "", index: 28, input: "JavaScript is more fun than Java or JavaBeans!"]
pattern.exec(test)
(2) ["JavaBeans", "Beans", index: 36, input: "JavaScript is more fun than Java or JavaBeans!"]

有分组的情况

 

　　　　

 

　　二、BootStrap

　　　　- CSS

　　　　- JS