Question

I’m using an online shopping cart which takes items ordered and passes their unique ID through the URL to a process.php page. So the URL would look something like

process.php?code_1=231&code_2=532&code_3=342

Another code_x=xxx is generated for each item ordered. On the process.php page, how would I create an array to get the values of the code_x without knowing how many items are ordered?

Answer 1

This problem is much better solved by changing the names of the elements in your form to code[].

For example, where you now have let’s say

<input type="text" name="code_1" ... />
<input type="text" name="code_2" ... />
<input type="text" name="code_3" ... />

You would change that to

<input type="text" name="code[]" ... />
<input type="text" name="code[]" ... />
<input type="text" name="code[]" ... />

After doing this, $_GET['code'] will be an array which contains all the values from the text boxes as its items.

Update:

If you cannot control the names of the incoming parameters, you need to parse manually. Here’s how I would do it:

// Sample data
$get = array('code_1' => 'foo', 'code_2' => 'bar', 'code_X' => 'X', 'asdf' => 'X');
$codes = array();

foreach($get as $k => $v) {
    // Reject items not starting with prefix
    if (substr($k, 0, 5) != 'code_') {
        continue;
    }

    // Reject items like code_X where X is not all digits
    $k = substr($k, 5);
    if (!ctype_digit($k)) {
        continue;
    }

    $codes[$k] = $v;
}

print_r($codes);