<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>正则</title>
</head>
<body>
<input type="text" id="regexp">
<script>
var $ = function(id){
return document.getElementById(id);
}
var addEvent = function(obj,event,fn){
if(obj.addEventListener){
obj.addEventListener(event,fn,false);
}else if(obj.attachEvent){
obj.attachEvent("on"+event,fn);
}
}
var regexp = $("regexp");
//test方法
/*var regexp = $("regexp");
addEvent(regexp,'change',function(){
//var pt1 = /^\d+$/g;
var pt1 = new RegExp('^\\d+$');
if(pt1.test(regexp.value)){
console.log(1);
}else{
console.log(0);
}
})*/
//replace方法
/*addEvent(regexp,'keyup',function(){
var pt2 = /\s/;
regexp.value = regexp.value.replace(pt2,'0');
})*/
//分支写法
/*addEvent(regexp,'change',function(){
var pt3 = /^([1-9]\d*(\.\d{2})?|0(\.\d{1,2})?)$/g;
if(pt3.test(regexp.value)){
console.log(1);
}else{
console.log(0);
}
})*/
//零宽断言
/*addEvent(regexp,'change',function(){
var pt4 = /\b\w+(?=ing\b)/g;//零宽度正预测先行断言
var pt5 = /(?<=\bre)\w+\b/g;//零宽度正回顾后发断言,js不支持
regexp.value = regexp.value.replace(pt5,'ccc');
})*/
</script>
</body>
</html>
