You can also use this javascript code for validating your email id :-
<script type="text/javascript">
function RegexEmail(emailInputBox){
var emailStr =
document.getElementById(emailInputBox).value;
var emailRegexStr =
/^[a-zA-Z0-9._-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,4}$/;
var isvalid =
emailRegexStr.test(emailStr);
if (!isvalid) {
alert('Invalid email
address!');
emailInputBox.focus;
}
}
</script>
<input name="emailInput"
id="emailInput" maxlength="60" />
<input id="btn1" type="button"
value="Validate Email" onclick="return
RegexEmail('emailInput')" />