Check empty fields with foreach

Question

I have a form system where the fields are generated by the base date through select. The same is done with foreach, how can I search the base date for the required fields and see if they have been filled in? And if they are not going to validate the form and show a message. NOTE: I don’t want to use required input.

<?php
if (isset($_POST['acao'])) {
    while (list ($key, $val) = each ($_POST)){ 
    mysql_query("insert into cms_formularios_respostas(usuario,resposta,campo,formulario) values('$name','".strip_tags($val)."','$key','$row[id]')") or die(mysql_error()); 
    }
}
?>
<form method="post" enctype="multipart/form-data" style="margin-bottom:5px"> 
<input type="hidden" name="acao" id="acao" value="<?php echo $row['id']; ?>" /> 
<?php
$get_form = mysql_query("SELECT * FROM cms_formularios_campos WHERE formulario = '$row[id]' ORDER BY ID") or die(mysql_error());
while($form = mysql_fetch_assoc($get_form)){
?><p><label class="label-form" for="<?php echo $form['id']; ?>"><?php echo $form['nome']; ?></label><br /><?php if($form['tipo'] == 'Resposta curta'){ ?><inputtype="text" name="<?php echo $form['id']; ?>" id="<?php echo $form['id']; ?>" class="input-form" /><br><?php if($form['obrigatorio'] == 'sim'){ ?><span style="color:red">* Requerido</span><?php } ?><?php } ?></p><input type="submit" class="input-form" value="Enviar" />

Answer 1

Starting with logic, you are creating a form dynamically, with the data coming from the database, legal, but the 'mandatory' field in the form column, will serve no purpose, when submitting the form to the server, we can take the global variable generated by your name, and its value, we cannot identify whether the input was mandatory or not.

So you have 2 alternatives, do a static validation, or a gambiarra to use the 'mandatory' field of the bank, I will demonstrate the first alternative.

php form.

<?php if(isset($_GET['empty'])){ ?>
  <strong id="empty">Erro! Favor preencher todos os campos!</strong>
<?php } ?>


<form action="valida.php" method="POST">

<input type="text" name="value1">

<input type="text" name="value2">

<input type="text" name="value3">

<input type="submit" value="enviar">

</form>

valida.php

<?php

//Caso value1 e value3 sejam obrigatórios.

if(empty($_POST['value1']) || empty($_POST['value3'])) {
     header( 'location: formulario.php?empty#empty' ); exit();
}

...

?>

I haven’t tested it, but it’s likely to work.

I will explain why the second alternative is unfeasible.

As I said before, not validating the client will bring numerous disadvantages, because, when submitting, you would have to search in the database the required fields, bringing some identifier attribute for the same, example an id (I believe you have this field because in your code it appears), this id would have to be according to the name of the form, so it would be checked, with a looping for each value, so you...

• You will lose the form data.
• It will lose in maintainability because it will be stuck to a rule.
• Lose in server requests and in performance.

Answer 2

It is very important, both in terms of usability and performance that you at least place the property required in your HTML in the required fields. This will cause the user to be informed in real time, with a message in the browser, about which fields he should fill in, and will also prevent your server from having to validate several unnecessary requests. It is also worth noting that even doing this on the client side, server validation is required. Never trust your customer’s data.

So, I stuck to the code regarding the validation of the form. If I understand correctly, the submission of the form will generate values of the type:

$_POST = [
    "acao" => "1",  // $row['id']
    "1" => ...,
    "2" => ...,
    "3" => ...,
];

Where the field acao is defined by the value of $row['id'] and the others refer to fields registered in the database. To find out which ones are mandatory, you will need to search the values again in the bank:

if ($_SERVER["REQUEST_METHOD"] == "POST")
{
    $formulario = filter_input(INPUT_POST, 'acao', FILTER_VALIDATE_INT);
    $query = mysql_query("SELECT id, nome FROM cms_formularios_campos WHERE formulario = '{$formulario}' and obrigatorio = 'sim' ORDER BY ID") or die(mysql_error());

    $erros = [];

    while($campo = mysql_fetch_assoc($query))
    {
        if (empty($_POST{$campo["id"]}))
        {
            // Algum campo obrigatório está em branco. Definir lógica do erro.
            $erros[] = "O campo {$campo['nome']} é obrigatório e não foi preenchido.";
        }
    }

    if (count($erros) === 0)
    {
        // Insere os valores da tabela de respostas
        // Utilize o input_filter ou filter_input_array para tratar os dados
    }
}

After that, you could display the error messages in the form by doing:

foreach($erros as $erro)
{
    echo "<div class='erro'>{$erro}</div>";
}

Important reading: Why should we not use mysql type functions_*?