<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<meta http-equiv="x-ua-compatible" content="IE=edge, chrome=1">
<title></title>
<style></style>
</head>
<body>
<input type="text" id="text" >
<script>
window.onload = function(){
var reg = /^(?=.*\d)(?=.*[a-zA-Z]).{4,}$/;
console.log(reg.test('1212aa1a1a11a1\n111'));
document.getElementById('text').onkeyup =function(){
var val =this.value;
console.log(reg.test(val));
}
}
</script>
</body>
</html>
是转义字符, n是换行的意思,
'1212aa1a1a11a1\\n111'
, 这里要加一个\
自动转义是肯定存在的