Validating Email address !!!

[waps]

Hi people,

I have found this script for validating an email address entered into a form field.
Yet it seems in complete. When you enter e.g. "[email protected]". It works. But when you put "[email protected]" it still works. So it needs a bit adding to it. In the script it checks to make sure there are characters after the '.', but it needs a section to check that there are characters before the '.' also. I have tried figuring it out, but to no evail. Any one help me with this little addition.

Thanks in advance




oops, forgot the code the first time round when posting, here it is !!!!!


function validEmail(email) {
invalidChars = " /:,;"

if (email == "") { // Cannot be empty
return false
}
for (i=0; i<invalidChars.length; i++) { // Does it contain any invalid characters
badChar = invalidChars.charAt(i)
if (email.indexOf(badChar,0) > -1) {
return false
}
}
atPos = email.indexOf("@",1) // There must be at least one '@' symbol
if (atPos == -1) {
return false
}
if (email.indexOf("@",atPos+1) != -1) { // And only one '@' symbol
return false
}
periodPos = email.indexOf(".",atPos) // at least one '.' after the '@'
if (periodPos == -1) {
return false
}
if (periodPos+3 > email.length) { // must be at least 2 characters after the '.'
return false
}
return true
}

[x_goose_x]

<script>
function check(eml) {
invalidChars = " /:,;"

msg = "";

for (x=0; x<invalidChars.length; x++) {
xchar = invalidChars.charAt(x);
xchar2 = eml.indexOf(xchar);
if (xchar2!=-1) {
msg += "Invalid character "+xchar+" used.\n";
}
}

eml2 = eml.split("@");
l = eml2.length;
if (l<2) {
msg += "Missing \"@\" symbol.\n";
}
else if (l>2) {
msg += "Cannot have more than one \"@\" symbol.\n";
}else{
eml3 = eml2[1].split(".");
l2 = eml3.length;
if (l2<2) {
msg += "Missing \".\" symbol.\n";
}
else if (l2>2) {
msg += "Cannot have more than one \".\" symbol in the sitename.\n";
}else{
if (eml3[0]=="") {
msg += "Invalid site name.\n";
}
else if (eml3[1]=="") {
msg += "invalid site extension.\n";
}
}
}
if (msg != "") {
alert(msg);
}else{
alert("Valid email");
}
}
</script>

[ضkii]

The smallest I could get a basic test that checks for
[character(s)] @ [character(s)] . [character(s)]

was

em = document.forms["reqs"].elements["email"].value;
tr = (em.indexOf("@",1)>0) ? em.indexOf(".",3) : -1;
if (tr<3) {
alert('bad email');
}

I'm sure a regex will do better though.

[valeria_vi]

Originally posted by ضkii
I'm sure a regex will do better though.

actually, somebody posted an email validation script using regexp on old boards a ong time ago. i think it was jkd. i only wished i had it saved. may be somebody has it.

[JohnKrutsch]

There is a regx one in this post:

http://www.codingforum.net/showthread.php?s=&threadid=291&highlight=email

[jkd]

How about http://www.javascriptkit.com/script/...2/acheck.shtml



It contains the monster RegExp I wrote a while ago when I was bored:
/^(\w+(?:\.\w+)*)@((?:\w+\.)*\w[\w-]{0,66})\.([a-z]{2,6}(?:\.[a-z]{2})?)$/i

(I'm quite proud of that beast )

[whammy]

That's a good one, jkd - but it said a friend of mine's email address, i.e.

[email protected]

was invalid... from what I understand (correct me if I'm wrong!) email addresses should also allow a hyphen in the first part before the @ ?

Anyway this one seems to work good:

/^[a-z0-9]+([-_\.]?[a-z0-9])[email protected][a-z0-9]+([-_\.]?[a-z0-9])+\.[a-z]{2,4}$/i

[jkd]

Ah, \w doesn't incorpoate hyphens, thanks for the tip. (Didn't think of email addies with hyphens):

var re = /^([\w-]+(?:\.[\w-]+)*)@((?:[\w-]+\.)*\w[\w-]{0,66})\.([a-z]{2,6}(?:\.[a-z]{2})?)$/i

Fixes that (I designed the RegExp especially to be used like:

re('[email protected]') == ['[email protected]', 'user', 'domain'. 'ext'];

(or re.exec(str) if that's more comfortable syntax, but in actuality all RegExp instances are really functions, interestingly enough)

That helps in validating certain parts of the address...

[whammy]

I'm still not totally convinced on the actual validation rules for email addresses, though...

Does anyone have a comprehensive article on what exactly a valid email address is?!?

I've looked and looked (since long before this post, fyi) and still... I've never found a comprehensive resource.

Thanks in advance.

[jkd]

I'm pretty sure it just consists of a valid *nix username, @, a valid subdomain/domain combination, a ., then 2-6 letters, then optionally followed by a dot and 2 letters.

[waps]

Hey thanks everyone for all your replys, I've put together a good email checker now from all of your input. Those regular expressions look pretty useful, must look into them abit more.

Anyway thanks very much

[waps]

Hi everyone,

Im trying to create a regular expression to validate a phone number. Here is what I got:

var te = /^([\d]+[?:\s][\d]+)$/

if (!te.test(Email_Form.Telephone.value)) {
alert ("Please enter your contact telephone number then re-submit the form")
return false
}

What it is suppos to do, is limit the input to just digits, which it does, but to allow a space character, if the user choices to pu one in. So in which case, this: 01333 844444 would be ok, so would 01333844444. It only seems to work when a space is there.

Any ideas ??

Thanks

[waps]

Ok, not to worry people, I figure my last problem out.

Here is what I should of put:

/^([\d?:\s]{11,})$/

Thanks anyway