表单$ _POST错误，动态字段

Question

I have an error that I can't figure out...

Om my webpage there is a form that the user has the ability to add some new input fields to. If the user is submitting the form, then the optional fields is empty when the php-file is handing them, why?

HTML:

        <form method="post" action="newRequest.php">
            <input type="text" name="title" />
            <input type="hidden" name="fname" value="0" />
            <input type="checkbox" name="fname" value="1"/>
            <input type="hidden" name="ename" value="0" />
            <input type="checkbox" name="ename" value="1" />
            <input type="hidden" name="seat" value="0" />
            <input type="checkbox" name="seat" value="1" />
            <input type="hidden" name="fields" value="0" />
            <input type="text" id="fields" name="fields" />
            <input type="submit" />
        </form>

PHP:

if (strlen($_POST[title]) > 2) {
    $toDb[title] = $_POST[title];
} else {
    error('title');
}

$toDb[fname] = $_POST[fname];
$toDb[ename] = $_POST[ename];
$toDb[seat] = $_POST[seat];

if ($_POST[fields] > 0) {
    $i = 0;
    while ($i < $_POST[fields]) {
        $toDb[optional][$i] = $_POST[optional-$i];
        $i++;
    }
    $toDb[optional] = serialize($toDb[optional]);
} else {
    $toDb[optional] = 0;
}
newEvent($toDb,$dbh);

JQuery that is adding dynamical fields:

$(document).ready(function() {
    $('#fields').focusout(function(){

        var fields = $('#fields').val();
        var i = 0;

        while(i < fields) {
            $('#fields').after("Valfritt fält "+(i+1)+":<input type='text' name='optional"+i+"' />");
            i++;
        }

    })
})

Answer 1

You should quote array indexes. It should be

 $toDb['optional'][$i] = $_POST['optional'.$i];