regular expression
- A regular expression used to match strings
Create a regular object
- Constructor
- var reg = new RegExp(regular expression, matching pattern);
new RegExp(pattern,attributes);
参数:参数pattern是一个字符串,指定了正则表达式的模式;
参数attributes是一个可选的参数,包含属性 g(globle全局匹配),i(忽略大小写),m(多行匹配)
- literal
- var reg = /regular rule/matching pattern;
Call matching method
- test most commonly uses a regular object to match a certain string
- If the match is successful, get true, otherwise false
- Regular object.test(string)
例:匹配字符串中出出现连续的三个小写a
var reg = new RegExp(/a{3}/);
console.log(reg.test("aaac")); //true
console.log(reg.test("baaab"));//true
console.log(reg.test("aa"));//false
console.log(reg.test("AAA"));//false
- match is used to match a certain string
- String.match(regular expression)
- Return value: array – containing the matched string and the index of the matched original string
例:匹配字符串中是否包含连续的三个小写a
console.log("aaabcdefaaaghjiy".match(/a{3}/));
- exec
- Used to match strings
- Regular object.exec(string) return value is the same as match
Intercept/replace a string between two characters
const str = '/detail/page-1.html'
str.match(/page-(\S*).html/)[1]
str.replace(/(?<=page-).*?(?=.html)/, 2)