How to submit on select

Question

I'm quite new to Javascript and i'm trying to find out how i submit on select and update the database.

I have this so far:

<form method="post">
<select name='myfield' onchange='form.submit()'>
<option>Select Weapon</option>
<option>AK47</option></select>
<noscript><input type="submit" value="Submit"></noscript>
</form>

But i have no idea how to update the database from here.

Answer 1 · 2014-06-18T10:30:30Z

June 18, 2014 10:30am

Hello,

Personally, I use JQuery to do this:

Give your form and select an id:

<form method="post" id="myform">
<select name='myfield' id="myfield">

Then at the bottom of your page, before the end of your body:

<script src="http://code.jquery.com/jquery-latest.min.js"></script>
<script>
$('#myfield').bind('change', function () {
    //post
    $("#myform").submit();
});
</script>

Your page will be reloaded and since your form uses the method POST, you can get the value of the select from the $_POST["myfield"] using PHP. (this "myfield" is the name of the name attribute, not the id, the id is for JQuery, PHP uses name):

<?php
$selectedvalue = $_POST["myfield"];
?>

You can further use PHP to update your Database with this value. Best is to use PDO, there's a course here. Something like this:

<?php
$selectedvalue = $_POST["myfield"];
//you'll probably need this for a specific user or something else?
$userid = 1;
updateDatabase($selectedvalue, $userid);

//preferable in another .php file:
function updateDatabase($selectedweapon, $userid) {
    require("_inc/database.inc.php");

    try {
        $query = "UPDATE T_User
                    SET myweapon = :selectedweapon
                                        WHERE userid = :userid";

        $results = $db_mnet->prepare($query);
        $results->bindParam(':selectedweapon',$selectedweapon,PDO::PARAM_STR);
                $results->bindParam(':userid',$userid,PDO::PARAM_INT);
        $results->execute();    
    } catch (Exception $e) {
                exit;
        }
}
?>

You could fill in the selected value again on reload in your select too:

<form method="post" id="myform">
<select name='myfield' id="myfield">
    <option>Select Weapon</option>
    <option <?php if (isset($selectedvalue) && ($selectedvalue == "AK47")) { echo "selected"; } ?>>AK47</option>
</select>
</form>

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Darrel Lyons

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How to submit on select

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Heidi Brebels

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Darrel Lyons

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