retreving value from database and displaying them in tree menu.

langsor · 2008-08-27T06:24:35+00:00

Okay, why do you have multiple accounts here?
On this thread you are posting as krishnareddi. On this other thread (http://www.daniweb.com/forums/thread142367.html) as sarithak -- why?

As I said in your other thread...
Okay, I did NOT test this, so who knows if it will actually work or what bugs, spelling, and syntax errors I have in it ... but this is the idea I would go with and you can check the errors to figure out what I did wrong.

<?php

// UNLOAD YOUR TALBES INTO ASSOCIATIVE ARRAYS
// this is not a good approach for large database tables
$parents = array();
$children = array();

// I'm assuming `cname` is a UNIQUE value across all records ... 
// no duplicate values for `cname`
$result = mysql_query("SELECT * FROM `addcourse`") or die(mysql_error());
while ( $assoc = mysql_fetch_assoc( $result ) ) {
  $parents[$assoc['cname']] = $assoc
}
mysql_free_result( $result );

$result = mysql_query("SELECT * FROM `subcourse` ORDER BY `cname`") or die(mysql_error());
while ( $assoc = mysql_fetch_assoc( $result ) ) { 
  $children[] = $assoc
}

// MAP CHILDREN TO PARENTS
foreach ( $children as $child ) {
  $key = $child['cname'];
  if ( array_key_exists( $key, $parents ) ) {
    if ( !array_key_exists( 'children', $parents[$key] ) ) {
      $parents[$key]['children'] = array();
    }
    $parents[$key]['childred'][] = $child;
  }
}

// PRINT OUT TREE STRUCTURE -- EDIT FOR YOUR SPECIFIC NEEDS
print "<ul>\n";
foreach ( $parents as $key => $parent ) {
  print "  <li>$key</li>\n"; // cname value
  if ( is_array( $parent['children'] ) {
    print "  <ul>\n";
    foreach ( $parent['children'] as $child ) {
      print "    <li>{$child['subcname']}</li>\n";
    }
    print "  </ul>\n";
  }
}
print "</ul>\n";

exit;
?>

Bye

krishnareddi 0 Newbie Poster · 2008-08-27T14:02:36+00:00

hey langsor, thanx for the help...but the problem is i cud print the values from database but wat i want is that the child menu shud appear only wen i click on the parent menu...so for that reaason i used js file..but nw i cud display the sub menu wen i click on the parent menu for only one category or for one parent menu item. i hope i made my query clear. help appreciated. thanx:)

langsor · 2008-08-27T21:53:58+00:00

If you only want to grab the values for the child parts of the tree when someone clicks on a parent item in the tree ... you have a couple options.

1. You can load all the parent and child values together into the page (like I've done above) and use JavaScript to show/hide the children when the parent is clicked on.
Pros: You can do this with only one page load.
Cons: It requires knowledge of JavaScript and requires most memory to store all database values.

2. You can submit a form when the user clicks on the parent and reload the page with that parent's child values associated with it.
Pros: You don't need any JavaScript
Cons: You must reload the page each time the user selects a parent-item

3. You can use Ajax to query the child elements and load them into the page, when the user clicks on a parent item.
Pros: Most elegant and fluid solution.
Cons: Requires greatest knowledge of JavaScript to implement.

What you can not do, is expect PHP to load the specific child values when the user clicks the parent item -- since the page is already loaded, PHP is done doing what it can do.

Hope this helps