change dropdown from array to check box - php

Question

I would like a change from the drop down to the checkbox, I want to change it because I want firstly select the list in the array can be selected before store to database via the checkbox, so the dropdown script was as follows
<?php
session_start();
define('DEFAULT_SOURCE','Site_A');
define('DEFAULT_VALUE',100);
define('DEFAULT_STC','BGS');
include('class/stockconvert_class.php');
$st = new st_exchange_conv(DEFAULT_SOURCE);
if(isset($_GET['reset'])) {
unset($_SESSION['selected']);
header("Location: ".basename($_SERVER['PHP_SELF']));
exit();
}
?>
<form action="do.php" method="post">
<label for="amount">Amount:</label>
<input type="input" name="amount" id="amount" value="1">
<select name="from">
<?php
$stocks = $st->stocks();
asort($stocks);
foreach($stocks as $key=>$stock)
{
if((isset($_SESSION['selected']) && strcmp($_SESSION['selected'],$key) == 0) || (!isset($_SESSION['selected']) && strcmp(DEFAULT_STC,$key) == 0))
{
?>
<option value="<?php echo $key; ?>" selected="selected"><?php echo $stock; ?></option>
<?php
}
else
{
?>
<option value="<?php echo $key; ?>"><?php echo $stock; ?></option>
<?php
}
}
?>
</select>
<input type="submit" name="submit" value="Convert">
</form>
and i Changed it to the checkbox as follows
<?php
session_start();
define('DEFAULT_SOURCE','Site_A');
define('DEFAULT_VALUE',100);
define('DEFAULT_STC','BGS');
include('class/stockconvert_class.php');
$st = new st_exchange_conv(DEFAULT_SOURCE);
if(isset($_GET['reset'])) {
unset($_SESSION['selected']);
header("Location: ".basename($_SERVER['PHP_SELF']));
exit();
}
?>
<form action="do.php" method="post">
<label for="amount">Amount:</label>
<input type="input" name="amount" id="amount" value="1"><input type="submit" name="submit" value="Convert">
<?php
$stocks = $st->stocks();
asort($stocks);
foreach($stocks as $key=>$stock)
{
if((isset($_SESSION['selected']) && strcmp($_SESSION['selected'],$key) == 0) || (!isset($_SESSION['selected']) && strcmp(DEFAULT_STC,$key) == 0))
{
?>
<br><input type="checkbox" id="scb1" name="from[]" value="<?php echo $key; ?>" checked="checked"><?php echo $stock; ?>
<?php
}
else
{
?>
<br><input type="checkbox" id="scb1" name="from[]" value="<?php echo $key; ?>"><?php echo $stock; ?>
<?php
}
}
?>
</form>
but does not work, am I need to display Other codes related?
Thanks if some one help, and appreciated it
UPDATED:
ok post the first apparently less obvious, so I will add the problem of error
the error is
Fatal error: Call to undefined method st_exchange_conv::convert() in C:\xampp\htdocs\test\do.php on line 21
line 21 is $st->convert($from,$key,$date);
session_start();
if(isset($_POST['submit']))
{
include('class/stockconvert_class.php');
$st = new st_exchange_conv(DEFAULT_SOURCE);
$from = mysql_real_escape_string(stripslashes($_POST['from']));
$value = floatval($_POST['amount']);
$date = date('Y-m-d H:i:s');
$_SESSION['selected'] = $from;
$stocks = $st->stocks();
asort($stocks);
foreach($stocks as $key=>$stock)
{
$st->convert($from,$key,$date);
$stc_price = $st->price($value);
$stock = mysql_real_escape_string(stripslashes($stock));
$count = "SELECT * FROM oc_stock WHERE stock = '$key'";
$result = mysql_query($count) or die(mysql_error());
$sql = '';
if(mysql_num_rows($result) == 1)
{
$sql = "UPDATE oc_stock SET stock_title = '$stock', stc_val = '$stc_price', date_updated = '$date' WHERE stock = '$key'";
}
else
{
$sql = "INSERT INTO oc_stock(stock_id,stock_title,stock,decimal_place,stc_val,date_updated) VALUES ('','$stock','$key','2',$stc_price,'$date')";
}
$result = mysql_query($sql) or die(mysql_error().'<br />'.$sql);
}
header("Location: index.php");
exit();
}
Why I want to change it from dropdown to checkbox?
because with via checkbox list I will be able to choose which ones I checked it was the entrance to the database, then it seem not simple to me, I looking for some help< thanks So much For You mate.

Answer 1

You have not removed the opening <select> tag.
But you removed the <submit> button.
You changed the name from "from" to "from[]".
EDIT: After your additions:
Using the dropdown list you were only able to select one value for from. Now you changed it to checkboxes and thus are able to select multiple entries. This results in receiving an array from[] in your script in do.php. Your functions there are not able to handle arrays or multiple selections in any way.
You have to re-design do.php, change your form back to a dropdown list or use ratio buttons instead.