<script language=”javascript”>
function checkEmail()

{

var email = document.getElementById(‘emailID‘);
var filter = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;
if (!filter.test(email.value))
{
alert(‘Invalid email address‘);
return false;
}
}
</script>

<input type=”text” name=”txt” id=”emailID” />
<input type=”button” name=”submit” onclick=”return checkEmail()” value=”Test”/>


function iVali(YourUrl)
{
var regUrl = /((ht|f)tp(s?)\:\/\/|~\/|\/)?(\w+:\w+@)?(([-\w]+\.)+(com|co.in|org|net|in|[a-z]{2}))(:[\d]{1,5})?(((\/([-\w~!$+|.,=]|%[a-f\d]{2})+)+|\/)+|\?|#)?((\?([-\w~!$+|.,*:]|%[a-f\d{2}])+=([-\w~!$+|.,*:=]|%[a-f\d]{2})*)(&([-\w~!$+|.,*:]|%[a-f\d{2}])+=([-\w~!$+|.,*:=]|%[a-f\d]{2})*)*)*(#([-\w~!$+|.,*:=]|%[a-f\d]{2})*)?/;

if (regUrl.test(YourUrl) == false)
return false
else
return true
}