[Resolved] have a feeling weve been here before - looping....

stevesweetland

right. i have a table ,

ID    MediumInt  Primary AutoIncrement
Name  VarChar(255)
Parent MediumInt
Level  MediumInt

In this table, i input records in, lets say

1 (id)
Menu 1 (name)
0 (parent)
0 (level)

2
Menu 2



3
Menu 1-a
1
1

4
Menu 1-b
1
1

5
Menu 1-b-a
4
2

the result being that i can loop the results, starting at the top, printing them to screen...

Menu 1
Menu 1 > Menu 1-a
Menu 1 > Menu 1-b
Menu 1 > Menu 1-b > Menu 1-b-a
Menu 2

the items are identified by not only the level, but by the parent - IE '5; Menu 1-b-a' parent is '4; Menu 1-b'.

thats all fine. RIIIIGHT, now you have the background, i want to put these into a drop down menu.

not a problem, just do (pseudo code) :

$sql = "select all your level 0 items";
loop all the level 0 items{
  print "your option tag for the drop-down form element";

  $sql = "select all the level 1 items where the parent is the same as the current level 0 id"
  loop all the relevant level1 items{
    print "your option tag for the drop-down form element";    

  };
};

none too dusty, i hear you cry... but wait - theres more.

whatever code I do, has to account for the fact we dont know how many levels there are, there is an unspecified number of levels (not unlimited, unspecified, as its specified by what the user may input).

the code i have suggested there, will only account for one level.

fix me! 😃

bubblenut

<?php
function getChildren($level=0,$id=false) {
  if($level==0) {
    $sql="SELECT * FROM menus WHERE level=0";
  } else {
    $sql="SELECT * FROM menus WHERE level=$level && parent_id=$parent";
  }
  $res=mysql_query($sql);
    for($i=0;$row=mysql_fetch_assoc($res);$i++){
    $output[$i]=$row;
    $output[$i]['children'] = getChildren($level+1,$row['unique_id']);
  }
  return $output;
}
$output=getChildren();
?>

Think that should do it. Recursion is definately the way even if my specific example is not. One thing you may want to do for the sake of optimization is to figure out a way where by you do not have to do a query every iteration as this could get very heavy very quickly.
HTH
Bubble

stevesweetland

oooo now thats a pretty bit of code... cheers bloke!