JS正则表达式比较常见用法

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废话不多说，直接步入正轨了，想要了解js正则表达式用法的相关知识，通过本教程学习吧。

定义和使用

var patt1 = new RegExp("hello"); 
var patt2 = /world/ ;

test方法

test() 方法检索字符串中的指定值。返回值是 true 或 false。

var pat = /my/; 
var str = "this is my code..."; 
console.log(pat.test(str)); // true

exec方法

exec() 方法检索字符串中的指定值。返回值是被找到的值。如果没有发现匹配，则返回 null。

var pat = /hello/; 
console.log(pat.exec("oh hello world")); //返还hello

正则表达式类型

/pattern/attributes
参数 attributes 是一个可选的字符串，常用属性 “g”、”i” ，分别用于指定全局匹配、区分大小写的匹配。

var str = "Visit Hunger"; 
var patt1 = /hunger/i; //不区分大小写 
console.log(str.match(patt1)); //全局匹配 
var str="hello hunger valley! I am hunger"; 
var patt1=/hunger/g; 
console.log(str.match(patt1)); //不区分大小写，全局匹配 
var str="hello Hunger valley! I am hunger"; 
var patt1=/hunger/gi; 
console.log(str.match(patt1));

字符串正则

1. search

字符串查找

var str="Visit W3School!"; 
console.log(str.search(/w3school/)); //-1 console.log(str.serach(/w3school/i)); // 6

2. match

字符串匹配

var str="1 plus 2 equal 33"; 
console.log(str.match(/\d+/)); //[1] 
console.log(str.match(/\d+/g)); //[1,2,33]

3. replace

字符串替换

var str="Hello JI! oh I am hunger" 
console.log(str.replace(/Hunger/, "valley")); console.log(str.replace(/hunger/ig, "hunger"));

4.split

字符串分割

var str = "Hello Hunger , oh I am Hunger"; 
str.split("");
str.split(/\s+/);

正则写法

"htmlcode">

var str="Is this all there is"; 
var patt1=/[a-h]/g;
console.log(str.match(patt1));

"htmlcode">

var str="hello jikexueyuan!"; 
var patt1=/[^jike]/g; 
console.log(str.match(patt1));

"htmlcode">

var str="hello hunger! How are you"; 
var patt1=/hello|you/g; c
onsole.log(str.match(patt1));

"htmlcode">

var str="That's hot!"; 
var patt1=/h.t/g; 
document.write(str.match(patt1));

"htmlcode">

var str="Give 100%!"; 
var patt1=/\w/g; 
document.write(str.match(patt1));

"htmlcode">

var str="Give 100%!"; var patt1=/\W/g; document.write(str.match(patt1));

"htmlcode">

var str="Give 100%!"; 
var patt1=/\d/g; 
document.write(str.match(patt1));

"htmlcode">

var str="Give 100%!"; var patt1=/\D/g; document.write(str.match(patt1));

"htmlcode">

var str="Is this all there is";
var patt1=/\s/g; document.write(str.match(patt1));

"htmlcode">

var str="Is this all there is"; var patt1=/\S/g; document.write(str.match(patt1));

"htmlcode">

var str="Hello jikexueyuan"; 
var patt1=/\bjikexueyuan/g; 
document.write(str.match(patt1));

"htmlcode">

var str="Hello Hunger.\n be a FE."; 
var patt1=/\n/g; document.write(str.search(patt1));

"htmlcode">

var str="Hello HHunger! Hello World!"; 
var patt1=/H+/g; 
document.write(str.match(patt1)); 
var str="Hello Hunger! Hello World!"; 
var patt1=/\w+/g; document.write(str.match(patt1));

"htmlcode">

var str="Hellooo Hunger! Hello World!"; var patt1=/lo*/g; document.write(str.match(patt1))

"htmlcode">

var str="1, 100 or 1000"; var patt1=/10"htmlcode">

var str="100, 1000 or 10000"; var patt1=/\d{4}/g; document.write(str.match(patt1)); 


"htmlcode">

var str="100, 1000 or 10000"; var patt1=/\d{3,4}/g; document.write(str.match(patt1)); 


"htmlcode">

var str="100, 1000 or 10000"; var patt1=/\d{3,}/g; document.write(str.match(patt1)); 


"htmlcode">

var str="Is this his"; var patt1=/is$/g; document.write(str.match(patt1)); 


"htmlcode">

var str="Is this his"; var patt1=/^Is/g; document.write(str.match(patt1)); 


常见正则
汉字： [\u4e00-\u9fa5] 

手机号： 1[0-9]{10} 

邮箱： (\S)+[@]{1}(\S)+[.]{1}(\w)+