Welcome to WuJiGu Developer Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
1.3k views
in Technique[技术] by (71.8m points)

arrays - PHP: nested menu with a recursive function, expand only some nodes (not all the tree)

I have this array, called $nested (it's a long one, but I tried to get a comprehensive scenario):

Array
(
    [1] => Array
        (
            [id] => 1
            [parent] => 0
            [title] => Page 1
        )

    [2] => Array
        (
            [id] => 2
            [parent] => 0
            [title] => Page 2
        )

    [3] => Array
        (
            [id] => 3
            [parent] => 0
            [title] => Page 3
        )

    [4] => Array
        (
            [id] => 4
            [parent] => 0
            [title] => Page 4
        )

    [5] => Array
        (
            [id] => 5
            [parent] => 0
            [title] => Page 5
        )

    [6] => Array
        (
            [id] => 6
            [parent] => 1
            [title] => Page 1-1
        )

    [7] => Array
        (
            [id] => 7
            [parent] => 1
            [title] => Page 1-2
        )

    [8] => Array
        (
            [id] => 8
            [parent] => 1
            [title] => Page 1-3
        )

    [9] => Array
        (
            [id] => 9
            [parent] => 2
            [title] => Page 2-1
        )

    [10] => Array
        (
            [id] => 10
            [parent] => 2
            [title] => Page 2-2
        )

    [11] => Array
        (
            [id] => 11
            [parent] => 2
            [title] => Page 2-3
        )

    [12] => Array
        (
            [id] => 12
            [parent] => 3
            [title] => Page 3-1
        )

    [13] => Array
        (
            [id] => 13
            [parent] => 3
            [title] => Page 3-2
        )

    [14] => Array
        (
            [id] => 14
            [parent] => 4
            [title] => Page 4-1
        )

    [15] => Array
        (
            [id] => 15
            [parent] => 6
            [title] => Page 1-1-1
        )

    [16] => Array
        (
            [id] => 16
            [parent] => 6
            [title] => Page 1-1-2
        )

    [17] => Array
        (
            [id] => 17
            [parent] => 6
            [title] => Page 1-1-3
        )

    [18] => Array
        (
            [id] => 18
            [parent] => 7
            [title] => Page 1-2-1
        )

    [19] => Array
        (
            [id] => 19
            [parent] => 7
            [title] => Page 1-2-2
        )

    [20] => Array
        (
            [id] => 20
            [parent] => 7
            [title] => Page 1-2-3
        )

    [21] => Array
        (
            [id] => 21
            [parent] => 9
            [title] => Page 2-1-1
        )

    [22] => Array
        (
            [id] => 22
            [parent] => 9
            [title] => Page 2-1-2
        )

    [23] => Array
        (
            [id] => 23
            [parent] => 9
            [title] => Page 2-1-3
        )

)

With this recursive function:

function recursive($parent, $array) {
    $has_children = false;
    foreach($array as $key => $value) {
        if ($value['parent'] == $parent) {       
            if ($has_children === false && $parent) {
                $has_children = true;
                echo '<ul>' ."
";
            }
            echo '<li>' . "
";
                echo '<a href="/page.php?id=' . $value['id'] . '">' . $value['title'] . '</a>' . " 
";
            echo "
";
                recursive($key, $array);
            echo "</li>
";
        }
    }
    if ($has_children === true && $parent) echo "</ul>
";
}

<ul><?php echo recursive(0, $nested); ?></ul>

I easily get this output:

So far so good.

Now, I would like NOT to show the whole tree at once, but going deeper when the user clicks on a page/subpage, like this:

URL: http://www.example.com/page.php, initial state ("expand" all items with parent = 0)


URL: http://www.example.com/page.php?id=1 (expand all items with parent = 1)


URL: http://www.example.com/page.php?id=6 (expand all items with parent = 6)

And so on

Seems a mission impossible to me, any help, please? Thanks in advance

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Answer

0 votes
by (71.8m points)

You're almost there. Just one small problem: instead of recursive($key, $array) you need recursive($key + 1, $array). Still, as said by others, this would be a lot nicer if you just generated the entire output with PHP and then controlled it all with javascript. Having the page reload every time the user clicks an item is really not a good user experience.


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome to WuJiGu Developer Q&A Community for programmer and developer-Open, Learning and Share
...