Javascript Validation
Try testing the following form with valid and invalid email addresses. The code uses javascript to match the users input with a regular expression.
The code
function validate(form_id,email) { var reg = /^([A-Za-z0-9_\-\.])+\@([A-Za-z0-9_\-\.])+\.([A-Za-z]{2,4})$/; var address = document.forms[form_id].elements[email].value; if(reg.test(address) == false) { alert('Invalid Email Address'); return false; } }
Usage
In the forms 'onsubmit' code call javascript:return validate('form_id','email_field_id')
<form id="form_id" method="post" action="action.php" onsubmit="javascript:return validate('form_id','email');"> <input type="text" id="email" name="email" /> <input type="submit" value="Submit" /> </form>
!You should not rely purely on client side validation on your website / web application, if the user has javascript disabled this will not work. Always validate on the server.
