PHP Dynamic menu with SQL

I've got the following problem, i have a sidemenu and based on a $_GET['cat'] it must show content.

So i called my function : function showCat($cat) , $cat = $_GET['cat'] .

The function showCat is this :

function showCat($cat){
$cat= mysql_real_escape_string($cat); 
connectDatabase();
$menuquery = mysql_query("SELECT c_id, c_naam FROM categorie WHERE c_parent = '0'");
    while ($row = mysql_fetch_array($menuquery))
    {
        $c_id = $row["c_id"];
        $c_naam = $row["c_naam"];
        $c_parent = $row["c_parent"];
        echo "<a href='producten.php?cat=$c_id'>$c_naam<br>";
            if ($cat == "0")
            {
            }
            else 
            {
                $query2 = mysql_query("SELECT c_id, c_naam, c_parent FROM categorie WHERE c_parent = '$cat' "); // 5
                while ($row2 = mysql_fetch_array($query2)) 
                {
                        $c_id2 = $row2["c_id"];     // 11
                        $c_naam2 = $row2["c_naam"]; // test

                        if ($c_id == $cat)
                        {
                            echo "<a href='producten.php?cat=$c_id2'>- $c_naam2<br>";
                        }
                        else
                        {
                            echo "<a href='producten.php?cat=$c_id2'>- $c_naam2<br>";
                            $query3 = mysql_query("SELECT c_id, c_naam, c_parent FROM categorie WHERE c_id = '$c_id2'");
                            while ($row3 = mysql_fetch_array($query3))
                            {
                                $c_id3 = $row3["c_id"];
                                $c_naam3 = $row3["c_naam"];
                                $c_parent3 = $row3["c_parent"];
                                if ("a" == "b")
                                {
                                    echo "<a href='producten.php?cat=$c_id3'>-- $c_naam3<br>";
                                }
                            }
                        }               
                }
            }
    }
echo "</h3>";

}

The table "Categorie" looks like this : c_id c_naam c_parent

The following things occur :

If i don't set $cat or set $cat to 1 or 3 the menu is like this :

• Item 1
• Item 2
• Item 3

If i set $cat to 2 (under 2 there is 4 and 5) the menu is like this :

• Item 1
• ~Item 4
• ~Item 5
• Item 2
• ~Item 4
• ~Item 5
• Item 3
• ~Item 4
• ~Item 5

If i want under item 4 an other item, lets say 6 and 7, and i set $cat to 4, the menu becomes :

• Item 1
• ~Item 6
• ~Item 7
• Item 2
• ~Item 6
• ~Item 7
• Item 3
• ~Item 6
• ~Item 7

What can i do to make it work so it can 开发者_StackOverflow中文版become :

• Item 1
• Item 2
• ~Item 4
• ~~Item 6
• ~~Item 7
• ~Item 5
• Item 3

I hope i'm clear.

Thank you in advance!

If it's not possible can someone give me an example how to get an menu which already is collapesed?

---

Some things that should be changed:

• if ($cat == "0" || $cat != $c_id) { } else { ...

If the current category in the loop is not the given $cat, you don't want to display the sub-items (or so i believe from what you say). So you should add that check to the if-clause.

• $query2 = mysql_query("SELECT c_id, c_naam, c_parent FROM categorie WHERE c_parent = '$c_id' ");

Don't get the children of the selected category, get the children of the category that's selected in the loop. At the moment, when you select 4, you retrieve the children of 4 in the second query instead of the third!

• $query3 = mysql_query("SELECT c_id, c_naam, c_parent FROM categorie WHERE c_parent = '$c_id2'");

Right now you're just getting the same category again instead of it's children.

As for a general remark, you might want to rewrite this in a recursive way, so you're not limited to a certain nesting depth.