// Try this regular Expression by ES6 function

const emailValidate = (email) => {
  const regexp= /^[\w.%+-]+@[\w.-]+\.[\w]{2,6}$/;
  return regexp.test(email);
}

您可以使用此 regex (从 w3 资源(与 W3C 无关):

/^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,3})+$/.test(emailValue)

如果您使用 Node,您可以在后端以及前端使用此功能。

我不知道其他背景语言,所以我不能对其他使用情况进行评估。

<pre>
**The personal_info part contains the following ASCII characters.
1.Uppercase (A-Z) and lowercase (a-z) English letters.
2.Digits (0-9).
3.Characters ! # $ % & ' * + - / = ? ^ _ ` { | } ~
4.Character . ( period, dot or fullstop) provided that it is not the first or last character and it will not come one after the other.**
</pre>
*Example of valid email id*
<pre>
yoursite@ourearth.com
my.ownsite@ourearth.org
mysite@you.me.net
xxxx@gmail.com
xxxxxx@yahoo.com
</pre>
<pre>
xxxx.ourearth.com [@ is not present] 
xxxx@.com.my [ tld (Top Level domain) can not start with dot "." ]
@you.me.net [ No character before @ ]
xxxx123@gmail.b [ ".b" is not a valid tld ]
xxxx@.org.org [ tld can not start with dot "." ]
.xxxx@mysite.org [ an email should not be start with "." ]
xxxxx()*@gmail.com [ here the regular expression only allows character, digit, underscore and dash ]
xxxx..1234@yahoo.com [double dots are not allowed
</pre>
**javascript mail code**

    function ValidateEmail(inputText)
    {
    var mailformat = /^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,3})+$/;
    if(inputText.value.match(mailformat))
    {
    document.form1.text1.focus();
    return true;
    }
    else
    {
    alert("You have entered an invalid email address!");
    document.form1.text1.focus();
    return false;
    }
    }

微软在 ASP.NET MVC 中提供的常规表达式是

/^[\w-]+(\.[\w-]+)*@([a-z0-9-]+(\.[a-z0-9-]+)*?\.[a-z]{2,6}|(\d{1,3}\.){3}\d{1,3})(:\d{4})?$/

我在这里写的,如果它是错误的 - 尽管它一直是完美的我的需求。

最好的一个 :D(RFC友好和没有错误“太复杂”) :

function    isMail(mail)
{
    pattuser = /^([A-Z0-9_%+\-!#$&'*\/=?^`{|}~]+\.?)*[A-Z0-9_%+\-!#$&'*\/=?^`{|}~]+$/i;
    pattdomain = /^([A-Z0-9-]+\.?)*[A-Z0-9-]+(\.[A-Z]{2,9})+$/i;

    tab = mail.split("@");
    if (tab.length != 2)
        return false;
    return (pattuser.test(tab[0]) && pattdomain.test(tab[1]));
}

使用常规表达式:

 /^[a-z][a-zA-Z0-9_.]*(\.[a-zA-Z][a-zA-Z0-9_.]*)?@[a-z][a-zA-Z-0-9]*\.[a-z]+(\.[a-z]+)?$/

例子:

function validateEmail(email) {
    var re = /^[a-z][a-zA-Z0-9_.]*(\.[a-zA-Z][a-zA-Z0-9_.]*)?@[a-z][a-zA-Z-0-9]*\.[a-z]+(\.[a-z]+)?$/;
    return re.test(email);
}

只允许 @,,