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Having Trouble Building a Site from Scratch

I keep getting the error: Warning: Invalid argument supplied for foreach() in /Applications/XAMPP/xamppfiles/htdocs/ijdb/admin/authors/authors.html.php on line 13

Does anyone know where I went wrong or where the book went wrong, here's the code:

<?php include_once $_SERVER['DOCUMENT_ROOT'] . '/ijdb/includes/helpers.inc.php'; ?> <!DOCTYPE html> <html lang="en"> <head> <meta charset="utf-8"> <title>Manage Authors</title> </head> <body> <h1>Manage Authors</h1> <p><a href="?add">Add new author</a></p> <ul> <?php foreach ($authors as $author): ?> <li> <form action="" method="post"> <div> <?php htmlout($author['name']); ?> <input type="hidden" name="id" value="<?php echo $author['id']; ?>"> <input type="submit" name="action" value="Edit"> <input type="submit" name="action" value="Delete"> </div> </form> </li> <?php endforeach; ?> </ul> <p><a href="..">Return to JMS home</a></p> </body> </html>

3 Answers

Randy Hoyt
Randy Hoyt
Treehouse Guest Teacher

I would guess that $authors is probably not an array at this point. Do you have any authors yet?

I've input 2 into the database but every time I try to load the page I get that message. I'm using two include files my index.php which: // Display author list include $_SERVER['DOCUMENT_ROOT'] . '/ijdb/includes /db.inc.php';

       $result = $pdo->query('SELECT id, name FROM   author');
    catch (PDOException $e)
      $error = 'Error fetching authors from the database!';
      include 'error.html.php';

    foreach ($result as $row)
      $authors[] = array('id' => $row['id'], 'name' =>                 $row['name']);

 include 'authors.html.php';
and a helpers.inc.php which:
function html($text)
 return htmlspecialchars($text, ENT_QUOTES, 'UTF-8');

function htmlout($text)
  echo html($text);

function markdown2html($text)
  $text = html($text);

  // strong emphasis
  $text = preg_replace('/__(.+?)__/s', '<strong>$1</strong>', $text);
  $text = preg_replace('/\*\*(.+?)\*\*/s', '<strong>$1</strong>',  $text);

 // emphasis
  $text = preg_replace('/_([^_]+)_/', '<em>$1</em>', $text);
  $text = preg_replace('/\*([^\*]+)\*/', '<em>$1</em>', $text);

  // Convert Windows (\r\n) to Unix (\n)
  $text = str_replace("\r\n", "\n", $text);
  // Convert Macintosh (\r) to Unix (\n)
  $text = str_replace("\r", "\n", $text);

  // Paragraphs
  $text = '<p>' . str_replace("\n\n", '</p><p>', $text) . '</p>';
    // Line breaks
   $text = str_replace("\n", '<br>', $text);

  // [linked text](link URL)
  $text = preg_replace(
   '<a href="$2">$1</a>', $text);

return $text;

function markdownout($text) { echo markdown2html($text); }

Randy Hoyt
Randy Hoyt
Treehouse Guest Teacher

Right before you call the template file, do this:


Does it have what you expect it to have? If not, then the problem is earlier in the code and you can work your way up.