如果一个字段不为空，那么所有字段都不为空

Question

Is there an efficient way of processing part of a form that has three input fields. If all are empty then don't do anything, but if one is filled, all must be filled.

At the moment I have this

if (isset($_POST['desc1']) && !empty($_POST['desc1'])){
$email_message .= $_POST['desc1']. " - " . $_POST['code1']. " - Amount: " .$_POST['quant1']."<br>";
$toadd .= $_POST['desc1']. " - " . $_POST['code1']. " - Amount: " .$_POST['quant1']."<br><br>"; 
}

Problem is they could have entered the desc1 but not the code1 or quant1 and it will fire anyway. If they entered code1 or quant1 and not the desc1 nothing will happen, which again is a problem, I would like to display this as an error and have them go back and try again.

Answer 1

There are many ways to go about this.

$required = array('desc1', 'code1', 'quant1');
$errors = array();
$fields_set = 0;

foreach ($required as $rq) {
    if (isset($_POST[$rq])) {
        $fields_set++;
    } else {
        $errors[$rq] = "{$rq} is not set...";
    }
}

$valid = ($fields_set == 0 || $fields_set == count($required)) ? true : false;

if ($valid) {
    // do stuff
} else {
    print_r($errors);
}