email validations suggestions are required

Question

Possible Duplicate:
Validate email address in Javascript?

I have javascript for email validation :

     //function to check emails
     function echeck(str) {
   var at="@"
   var dot="."
   var lat=str.indexOf(at)
   var lstr=str.length
   var ldot=str.indexOf(dot)
   if (str.indexOf(at)==-1){
     return false;
   }

   if (str.indexOf(at)==-1 || str.indexOf(at)==0 || str.indexOf(at)==lstr){
   return false;
   }

   if (str.indexOf(dot)==-1 || str.indexOf(dot)==0 || str.indexOf(dot)==lstr){
    return false;   }

    if (str.indexOf(at,(lat+1))!=-1){
    return false; }

    if (str.substring(lat-1,lat)==dot || str.substring(lat+1,lat+2)==dot){
    return false; }

    if (str.indexOf(dot,(lat+2))==-1){
    return false;    }

    if (str.indexOf(" ")!=-1){
    return false;
   }

    return true;                    
    }

It working fine but not checking this one -> !!!!!!!!!@####.com

Kindly help me to check extra spl characters in email.

Regards,

Is the answer you seek not [here](http://stackoverflow.com/questions/46155/validate-email-address-in-javascript)? Beaten by @Mark Biek by 19 seconds :-( — Xav, Aug 17 '11 at 15:09
Screw validation. With all sorts of weird TLDs and non-ASCII character sets in domains nowadays, any validation beyond `*@*` is completely useless — Pekka, Aug 17 '11 at 15:22

Aleks G · Accepted Answer · 2011-08-17T16:25:12.913

The example you provided is not a valid email address at least because ####.com is not a valid domain name. What you really should do is use regular expression to check the email address.

The most simple version of the regex would be

/^[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,4}$/

and a much more complete one would be

/^[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*@(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\.)+(?:[A-Z]{2}|com|org|net|edu|gov|mil|biz|info|mobi|name|aero|asia|jobs|museum|xxx)$/

and the official RFC2822 implementation would be

/^(?:[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*|"(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x21\x23-\x5b\x5d-\x7f]|\\[\x01-\x09\x0b\x0c\x0e-\x7f])*")@(?:(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?|\[(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?|[a-z0-9-]*[a-z0-9]:(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x21-\x5a\x53-\x7f]|\\[\x01-\x09\x0b\x0c\x0e-\x7f])+)\])$/

And you would actually check the email address like so:

function echeck(str)
{
    //using the most simple version
    //substitute for another pattern if more complete matching is required
    var expr = /^[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,4}$/i;
    return expr.test(str);
}

Note that it's not a good idea to just do validation in JS. You should always perform another validation in the server - to prevent somebody passing bad data into your script and you happily using it. Keep in mind that you can't guarantee that the form will be submitted from your page.

email validations suggestions are required

1 Answers1