如何在javascript中验证电子邮件

Question

I am working on a mvc 5 project .in contact us page I want user to send admin his / her emaiul address .so I want to validate email in javascript on that page .I wrote some code that does not work properly. I want you to help me plesae.

<script language="javascript">
    function f1() {
        var inputText = document.getElementById("email").value;
        var mailformat = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;
        if (inputText.value.match(mailformat)) {
            document.form1.text1.focus();

        }
        else {
            alert("You have entered an invalid email address!");
            document.form1.text1.focus();
            event.preventDefault();
        }
    }
</script>

Answer 1

function validateEmail(email) {
    var re = ([\w-+]+(?:\.[\w-+]+)*@(?:[\w-]+\.)+[a-zA-Z]{2,7});
    return re.test(email);
}

Answer 2

A basic HTML and JS working code for validating email with JS is given here for u-

 function validateForm() { var x = document.forms["myForm"]["email"].value; var atpos = x.indexOf("@"); var dotpos = x.lastIndexOf("."); if (atpos<1 || dotpos<atpos+2 || dotpos+2>=x.length) { alert("Not a valid e-mail address"); return false; } else { alert("Valid e-mail address"); return true; } }

 <form name="myForm" action="demo_form.asp" onsubmit="return validateForm();" method="post"> Email: <input type="text" name="email"> <input type="submit" value="Submit"> </form>

Think, u have your answer :)

Answer 3

<form name="form" action="#" onSubmit="return f1()" method="POST">
    <input type="email">
</form>
<script>
function f1(){
    var email = document.forms["form"]["Email"].value;
    var regex = /^([0-9a-zA-Z]([-_\\.]*[0-9a-zA-Z]+)*)@([0-9a-zA-Z]([-_\\.]*[0-9a-zA-Z]+)*)[\\.]([a-zA-Z]{2,9})$/;
    if(!regex.test(email)){
        alert("You have entered an invalid email address!");
        return false;
    }
}  
</script>       

Answer 4

You don't want inputText.value only inputText like this

 <input type="text" id="email" /> <input type="submit" onClick="f1()"/> <script language="javascript"> function f1() { console.log(document.getElementById("email").value); var inputText = document.getElementById("email").value; console.log(inputText) var mailformat = /^([a-zA-Z0-9_\\.\\-])+\\@(([a-zA-Z0-9\\-])+\\.)+([a-zA-Z0-9]{2,4})+$/; if (inputText.match(mailformat)) { // <<<<<<< here //document.form1.text1.focus(); alert("correct") } else { alert("You have entered an invalid email address!"); document.form1.text1.focus(); event.preventDefault(); } } </script>