<script>
function checkForm(){
var email=document.emailform.email.value;
var pattern=/^([a-zA-Z0-9])+@([a-zA-Z0-9])+\.([a-zA-Z0-9])+/;
flag=pattern.test(email);
if(flag)
{
return ture;
}
else{
alert('不是合法的郵件格式!');
document.emailform.email.focus();
return false;
}
}
</script>