PHP echoing categories(parent) and sub categories(child)

[dk4210]

Hello Guys,

 

Need a little help here. I have a db structure like this

 

cat_id |  cat_name | cat_status | parent_id

1     First Test        1                  0

2     Just testing   1                 0

4     Books           1                 2

5     Cars           1                 0

6     Ford           1              5

 

If the parent_id = 0 it is considered to be the parent.

If it is a number it is considered a child and referencing the parent

 

I want to be able to query the database and grab the cat and the sub cat and echo it on my page. Its like a classified ads application.

 

Here is my while loop that I currently have which only echo's out the parent category. I would like to echo the child category under the respective parent category.

 

I think I would have to do a loop within a loop, but not sure how to do it..

 

$query  = "SELECT * FROM ad_category WHERE cat_status='1' && Parent_id='0' ORDER BY cat_name";
		$result = mysql_query($query);

			while($row = mysql_fetch_row($result))
			{
			   
			    $cat_name = $row[1];
			    

				$cupper = UCWords($cat_name);

			    echo $cupper . "<br>" ;
			    
			        
			} 

 

 

Thanks for your help in advance

[johnny86]

Here are two functions that are ready-made, you'll have to modify them just a little bit for your needs but it's not a biggie.

http://articles.sitepoint.com/article/hierarchical-data-database

[dk4210]

I found this code but I cant seem to get it to work right. The issue is that if the parent id =0 than its the parent. If its some other number it is considered to be the child and it is referencing the parent.

 

$nav_query = MYSQL_QUERY("SELECT * FROM ad_category WHERE cat_status='1' && Parent_id='0' ORDER BY cat_name");
$tree = "";                         // Clear the directory tree
$depth = 1;                         // Child level depth.
$top_level_on = 1;               // What top-level category are we on?
$exclude = ARRAY();               // Define the exclusion array
ARRAY_PUSH($exclude, 0);     // Put a starting value in it

WHILE ( $nav_row = MYSQL_FETCH_ARRAY($nav_query) )
{
     $goOn = 1;               // Resets variable to allow us to continue building out the tree.
     FOR($x = 0; $x < COUNT($exclude); $x++ )          // Check to see if the new item has been used
     {
          IF ( $exclude[$x] == $nav_row['cat_name'] )
          {
               $goOn = 0;
               BREAK;                    // Stop looking b/c we already found that it's in the exclusion list and we can't continue to process this node
          }
     }
     IF ( $goOn == 1 )
     {
          $tree .= $nav_row['cat_name'] . "<br>";                    // Process the main tree node
          ARRAY_PUSH($exclude, $nav_row['cat_id']);          // Add to the exclusion list
          IF ( $nav_row['cat_id'] < 6 )
          { $top_level_on = $nav_row['cat_id']; }

          $tree .= build_child($nav_row['cat_id']);          // Start the recursive function of building the child tree
     }
}

FUNCTION build_child($oldID)               // Recursive function to get all of the children...unlimited depth
{
     GLOBAL $exclude, $depth;               // Refer to the global array defined at the top of this script
     $child_query = MYSQL_QUERY("SELECT * FROM `ad_categoy` WHERE parent_id=" . $oldID);
     WHILE ( $child = MYSQL_FETCH_ARRAY($child_query) )
     {
          IF ( $child['cat_id'] != $child['parent_id'] )
          {
               FOR ( $c=0;$c<$depth;$c++ )               // Indent over so that there is distinction between levels
               { $tempTree .= " "; }
               $tempTree .= "- " . $child['title'] . "<br>";
               $depth++;          // Incriment depth b/c we're building this child's child tree  (complicated yet???)
               $tempTree .= build_child($child['cat_id']);          // Add to the temporary local tree
               $depth--;          // Decrement depth b/c we're done building the child's child tree.
               ARRAY_PUSH($exclude, $child['cat_id']);               // Add the item to the exclusion list
          }
     }

     RETURN $tempTree;          // Return the entire child tree
}

ECHO $tree;

[dk4210]

Thanks for the help, but I found something that works really well..

 

http://www.codeassembly.com/How-to-display-infinite-depth-expandable-categories-using-php-and-javascript/