/^([0-9a-zA-Z-]+)@([0-9a-zA-Z-]+)+((.[0-9a-zA-Z_-]{2,3}){1,2})$/g
//小程序用户请移步网页端查看,原文链接https://hkiii.cn/?post=84;
<body>
<input style="width:100%;" id="emailreg" placeholder="请输入一个邮箱地址"/>
<p id="emailp">
</p>
<button id="emailyz">验证</button>
</body>
<script>
document.getElementById("emailyz").onclick=function(){
var email = document.getElementById("emailreg").value;
console.log(email);
var reg = /^([0-9a-zA-Z_-]+)@([0-9a-zA-Z_-]+)+((\.[0-9a-zA-Z_-]{2,3}){1,2})$/gi;
var jieguo = reg.test(email);
console.log(jieguo);
if(jieguo == true){
document.getElementById("emailp").innerHTML="验证成功!"
}else{
document.getElementById("emailp").innerHTML="验证失败!"
}
}
</script>