Multilevel list

hanifl

I tried to make a multilevel of list. For example, I need a list of books divided by categories like:

Category: Since.
Tilte1
Tilte2

Category: History
Tilte1

Tilte2

What I have is:

Category: Since.
Tilte1

Category: Since.
Tilte2

Category: History
Tilte1

Category: History

Tilte2

I wrote this code:

$sql = "SELECT books.title, books.categoryid, categories.id, categories.category FROM books, categories
WHERE books.categoryid = categories.id
ORDER BY books.categoryid
";

$result = mysql_query($sql, $connection);

$dsp = "<ul>";

while ($row = mysql_fetch_array($result))
{
$title = $row['title'];
$category = $row['category'];

	$dsp .= "<li><b>$category</b>";

	if ($categoryid = $id)
		{
			$dsp = "<ul>";
			While ($row = mysql_fetch_array($result))
			{
				$dsp .= "<li>$title";
			}
			$dsp = "</ul>";
		}
}

$dsp .= "</ul>";

echo ("$dsp");

kparker

It's up to you to detect that a new category has arrived, and format things accordingly. Usually, it's sufficient to just track the category in a separate variable, e.g.:

$prev_cat = '';

while ($row = mysql_fetch_array($result))
   {
   if ( $row['category'] != $prev_cat )
      {
      // display new category
      }
   $title = $row['title'];
   ...
   $prev_cat = $row['category'];
   }

hanifl

Thanks