单选按钮值：“on”

i have this form, when user clicks on the submit button, a script open a popup where i need to print the radio button value. My problem is the printed value on the popup window: "on" but the result should be a number (selected person's id)

My PHP Code:

    <form method="post" action="edit.php" onsubmit="target_popup(this,'edit.php')"><input type="submit" value="Modifica Giocatore"  /><br /><br /><br />
                <?php
                    //my queries (work)
                ?>

                <table cellspacing="2" cellpadding="2">
                <tr>
                <th></th>
                <th>Name</th>
                <th>Surname</th>
                </tr>

                <?php
                    $i=0;
                    while ($i < $num) {
                        $id=mysql_result($results,$i,"ID");
                        $name=mysql_result($results,$i,"Name");
                        $surname=mysql_result($results,$i,"Surname");
                ?>

                <tr>
                    <td><input type="radio" name="radioEdit" value"<?= $id; ?>"  /><?= $id; ?></td>
                    <td><?=$name?></td>
                    <td><?=$surname?></td>
                </tr>


                <?php 
                    $i++; 
                    } 
                ?> 

                <?php

                    echo "</table></form>"
                ?>

And this is my script:

    function target_popup(form,page) 
    {
        window.open(page, 'formpopup', 'left=100,top=100,width=600,height=400,menubar,toolbar,resizable');
        form.target = 'formpopup';
    }

edit.php file:

    <?php
        $prova = $_POST['radioEdit'];
        echo $prova;        
    ?>

Thanks.

The only way I could get this to work was to use sessions.

Here is what I could test without setting up an entire DB.

PHP

<?php
session_start();
$id="12345"; // test ID number

// works with sessions
$prova = $_POST['radioEdit'] = $_SESSION['id'] = $id;
echo $prova;
?>

<form method="post" action="edit.php" onsubmit="target_popup(this,'edit.php')">
<td><input type="radio" name="radioEdit" value"<?php echo $id; ?>"  /><?= $id; ?></td>
<input type="submit" value="Modifica Giocatore"  />
</form>

<script>
    function target_popup(form,page) 
    {
        window.open(page, 'formpopup', 'left=100,top=100,width=600,height=400,menubar,toolbar,resizable');
        form.target = 'formpopup';
    }
</script>

edit.php

<?php
session_start();
echo $_SESSION['id'];
echo $id;
echo "<br>";
var_dump($_SESSION['id']);
?>

What happens when you echo $id? Are you sure that it returns a value? Also isn't <?= ;?> considered really old and deprecated PHP? You should be using <?php echo ;?>