Format my JSON string into an ordered list in PHP

Question

I\'m working on a simple CMS for a pet project. I currently have a JSON string that contains a list of page ID\'s and Parent page ID\'s for a menu structure.

I want to n

Answer 1

What you're looking for is called recursion, which can be done by a function calling itself.

If you solved once to list all nodes of the list in one function, you can then apply the same function for all child-lists. As then those child-lists will do the same on their children, too.

call_user_func(function ($array, $id = 'id', $list = 'children') {
    $ul = function ($array) use (&$ul, $id, $list) {
        echo '
', !array_map(function ($child) use ($ul, $id, $list) {
            echo '
', $child[$id], isset($child[$list]) && $ul($child[$list])
                  , '
';
        }, $array), '
';
    };
    $ul($array);
}, json_decode('[{"id":3,"children":[{"id":4,"children":[{"id":5}]}]},{"id":6},
                {"id":2},{"id":4}]', TRUE));

As this example shows, the $ul function is called recursively over the list and all children. There are other solutions, but most often recursion is a simple method here to get the job done once you've wrapped your head around it.

Demo: https://eval.in/153471 ; Output (beautified):

  
3
    

      
4
        

          
5
        
      
    
  
  
6
  
2
  
4