[PHP]代码
<?php
session_start();
$_SESSION['num'] = 0;
if(isset($_POST['action'] && $_POST['action']=='submit')){
if($_SESSION['num'] == 0){
echo '<a href="'.$_SERVER['PHP_SELF'].'">'请再次尝试</a>;'
$_SESSION['num'] = 1;
}else{
echo '您已经提交过了,请不要重复提交';
}
}
?>



















