How to loop over a multidimensional objectArray with Smarty?

In Smarty, how can I iterate over the sub value in my second foreach?

[test] => stdClass Object
        (
            [parent] => Test
            [sub] => Array
                (
                    [0] => Array
                        (
                            [key1] => Value 1
                            [key2] => Value 2
                        )

                )

        )
        
 {foreach from=$menuList item=menu}
    <li><a href="#">{$menu->name}</a>
        <ul class="dropdown-menu">
          {foreach from=$menu->sub key=k item=v}
                <li class="dropdown-submenu" name=>{$v}</li>
          {/foreach}
        </ul>
    {/foreach}
 </li>

How to print second foreach key and value?

It print array string only

First of all your "array" is in fact object. You need to convert it to array first to use that function. Here is a function that can do this:

function objectToArray($d) {
    if (is_object($d)) {
        // Gets the properties of the given object
        $d = get_object_vars($d);
    }
    if (is_array($d)) {
        /*
        * Return array converted to object
        * Using __FUNCTION__ (Magic constant)
        * for recursive call
        */
        return array_map(__FUNCTION__, $d);
    }
    else {
        // Return array
        return $d;
    }
}

Obviously this is php function, put it in php file or in smarty plugin to be able to access it. Then, here is a function that is using the previous function to deal dinamically with objects, or whatever input is.

function smarty_function_tree($params, &$smarty) {
if (!isset($params['level'])) {
    $level = 0;
    } else {
    $level = $params['level'];
}
return tree($params['data'], $level);
}

function tree($data, $level) {
echo '<ul class="level', $level, '">', "\r\n";
$aData = objectToArray($data);
foreach ($aData as $key => $entry) {
    if (is_array($entry)) {
        echo '<li>', $key, '</li>', "\r\n";
        tree($entry, $level+1);
    } else {
        echo '<li>', $key, ' = ', $entry, '</li>', "\r\n";
    }
}
    echo '</ul>', "\r\n";
}

Create a plugin called accordingly to function name, then you can use it in template like this:

{tree data=$yourObject}

or

{tree data=$yourArray}

Edit: you also can use litlebit of css to indent the output of the tree function:

.level0 {
    text-indent: 20px;
}

.level1 {
    text-indent: 40px;
}

.level2 {
    text-indent: 60px;
}

.level3 {
    text-indent: 80px;
}

.level4 {
    text-indent: 100px;
}

.level5 {
    text-indent: 120px;
}

.level6 {
    text-indent: 140px;
}

.level7 {
    text-indent: 160px;
}

.level8 {
    text-indent: 180px;
}

.level9 {
    text-indent: 200px;
}

Hope it helps!