使用 PHP 的单选按钮中的必填字段验证

Question

I am trying to add required field validation to a page where there are 5 radio buttons with the same name. If the user clicks the button to proceed to the next page an error should be displayed, below is the code I am currently using but it is not doing anything

<?php
if (empty($_POST) === false) {
$required_fields = array('q1');
foreach($_POST as $key=>$value) {
if (empty($value) && in_array($key, $required_fields) === true) {
    $errors[] = 'Please select a number between 1-5';
    break 1;
    }
}
if (empty($errors) === true) {
    if(!isset($_POST['q1'])){ 
    $errors[] = "Please select a number between 1-5"; 
} 

}
}
?>      

<h1>Assessment</h1>

<?php
if (isset($_GET['success']) && empty($_GET['success'])) {

} else {
if (empty($_POST) === false && empty($errors) === true) {
$updateassessment = array(
    'q1'                => $_POST['q1'],
);

updateassessment($updateassessment);
header ('Location: question2.php');
exit();

} else if(empty($errors) === false){
echo output_errors($errors);
}
?>

<form action="" method="post">

<p class="p1">
Question 1</p>
<p class="p4">
<?php
$result = mysql_query("SELECT * FROM traits WHERE Question = 'q1'");

while($row = mysql_fetch_array($result))
  {
  echo $row['fromtrait'] . ' - ' . $row['totrait'];
  echo "<br />";
  }


?></p>

<p class="p3">
<input type="radio" name="q1" value="1" />
1
<input type="radio" name="q1" value="2" />
2
<input type="radio" name="q1" value="3" />
3
<input type="radio" name="q1" value="4" />
4
<input type="radio" name="q1" value="5" />
5


</p><br><br>
  <input type="image" src="Images/image1.png" name="submit" align="right"/>
</form>

I got this to work by adding

if (empty($errors) === true) {
    if(!isset($_POST['q1'])){ 
    $errors[] = "Please select a number between 1-5"; 
} 

}

Answer 1

You have to set action="" to action=" <filename> " (in your form) else PHP won't know where to "go" after user submits the form. Filename refers to the php-file.

Answer 2

by it's nature PHP is a inefficient way to validate forms because the page has to reload for any PHP checks to be done. perhaps a client side solution can be implemented, but if not try this to see if it does what you're looking for...

$required_fields = array('q1');
foreach ($required_fields as $field) {
    if (isset($_POST[$field]) && !empty($_POST[$field])) {
         echo $field." was set<br>\n";
    } else {
        echo "validation for $field failed!<br>\n";
    }
}

Also... is Javascript an option? jquery ValidationEngine is quite useful and has checks for many of your field requirements, and validate before the form is submitted to mitigate needs tor PHP to do the checks.