I am developing an accounting system where users can add journal entries with dynamic rows for account, debtor, creditor, description, and acc_serial. However, when I add a new dynamic row and submit the form, the script throws an error:

An error occurred while processing data. Please try again.

This issue seems to arise because the arrays in the POST request (account, debtor, creditor, description, and acc_serial) have mismatched counts.

What I’ve tried:

PHP server-side validation

I added a validation step to ensure that all arrays (account, debtor, creditor, description, and acc_serial) have the same count:

if (count($_POST['account']) !== count($_POST['debtor']) || 
    count($_POST['account']) !== count($_POST['creditor']) || 
    count($_POST['account']) !== count($_POST['description']) || 
    count($_POST['account']) !== count($_POST['acc_serial'])) {
    
    echo '';
    exit;
}

This triggers the error message when the counts don’t match.

Debugging POST data

I used var_dump($_POST) to inspect the submitted data. Here’s the output for a problematic request:

 array (size=15)
  'date' => string '2024-12-09' (length=10)
  'entry_num' => string 'JE-0001' (length=7)
  'descrip' => string '6565' (length=4)
  'company' => string 'sahat' (length=5)
  'auth_token' => string '2582f394f3dab3ac3f139d1f7e715d6181ad182a' (length=40)
  'serial' => string '3CWZE7B8ZSVIO71Q440HT6HWX1RWKY3B8EL' (length=35)
  'j_type' => string 'Manual Entry' (length=15)
  'account' => 
    array (size=3)
      0 => string 'd59f127d86' (length=10)
      1 => string 'd5a05ca920' (length=10)
      2 => string 'd59fb74cb8' (length=10)
  'debtor' => 
    array (size=2)
      0 => string '2000' (length=4)
      1 => string '0' (length=1)
  'creditor' => 
    array (size=2)
      0 => string '0' (length=1)
      1 => string '1000' (length=4)
  'description' => 
    array (size=2)
      0 => string 'General Expense' (length=19)
      1 => string 'General Expense' (length=19)
  'acc_serial' => 
    array (size=2)
      0 => string 'd59f127d86' (length=10)
      1 => string 'd59fb74cb8' (length=10)

Account has 3 items, while debtor, creditor, description, and acc_serial have only 2 items.

PHP loop for processing rows

foreach ($_POST['account'] as $index => $value) {
    if (isset($_POST['account'][$index], $_POST['debtor'][$index], $_POST['creditor'][$index], $_POST['description'][$index], $_POST['acc_serial'][$index])) {
        $account = $_POST['account'][$index];
        $debtor = $_POST['debtor'][$index];
        $creditor = $_POST['creditor'][$index];
        $description = $_POST['description'][$index];
        $acc_serial = $_POST['acc_serial'][$index];
        
        if (empty($account) || empty($description) || empty($acc_serial) || $debtor === "" || $creditor === "") {
            echo '';
            exit;
        }

        if (!is_numeric($debtor) || !is_numeric($creditor)) {
            echo '';
            exit;
        }
    } else {
        echo '';
        exit;
    }
}

HTML structure for dynamic rows

JavaScript for adding dynamic rows:

$("#add-btn").click(function() {
    let i = $("#dynamicAddRemove tbody tr").length;
    
    $("#dynamicAddRemove").append('' +
        '' +
        '' +
        '' +
        '' +
        '' +
        'Remove' +
    '');
});

What could cause this mismatch in field counts when adding dynamic rows?

How can I debug or fix this issue to ensure all fields are submitted correctly?