如何迭代嵌套数组

Question

以下是我所拥有的：

$nav = array (
    "page 1" => array (
        "page 1.1" => array (
            "page 1.1.1"
            "page 1.1.2"
        ) ,
        "page 1.2"
    )
    "page 2" => array (
        "page 2.1"
    )
);

这就是我想要的：

<nav>
    <ul>
        <li>page 1
            <ul>
                <li>page 1.1
                    <ul>
                        <li>page 1.1.1</li>
                        <li>page 1.1.2</li>
                    </ul>
                </li>
                <li>page 1.2</li>
            </ul>
        </li>
        <li>page 2
            <ul>
                <li>page 2.1</li>
            </ul>
        </li>
    </ul>
</nav>

到目前为止我所拥有的：

foreach ($nav as $key => $val) {
    if (!is_numeric($key)) {
        $nav_entry = $key;
    } else {
        $nav_entry = $val;
    }
    echo "<li>" . $nav_entry . "</li>";
}

我的问题是，如果存在子数组，我需要有foreach循环。最重要的是，我需要以某种方式放入if语句，以添加<ul></ul>标记。。。

我开始看到星星。。。太令人困惑了。

Answer 1

试试：(

function createMenu($nav){
    echo "<ul>";
    foreach($nav as $key => $row){
        if(!is_array($row)){
            echo "<li>".$row."</li>";
        }else{
            echo "<li>".$key;
                createMenu($row);
            echo "</li>";
        }
    }
    echo "</ul>";
}
createMenu($nav);

Answer 2

尝试

<?php
$nav = array (
    "page 1" => array (
        "page 1.1" => array (
            "page 1.1.1",
            "page 1.1.2"
        ),
        "page 1.2"
    ),
    "page 2" => array (
        "page 2.1"
    )
);
function drawRecursive($list){
    echo "<ul>";
    foreach ($list as $key=>$item){
        echo "<li>";
        if (is_array($item)){
            echo $key;
            drawRecursive($item);
        } else {
            echo $item;
        }
        echo "</li>";
    }
    echo "</ul>";
}
echo "<nav>";
drawRecursive($nav);
echo "</nav>";
?>

Answer 3

$array = [
    'home',
    'page 1' => [
        'page 1.1' => [
            'page 1.1.1',
            'page 1.1.2'
        ],
        'page 1.2'
    ],
    'page 2' => [
        'page 2.1'
    ]
];
function buildLists($array) {
    $result = '';
    foreach($array as $key => $value) {
        if(!is_int($key)) {
            $result .= '<li>' . $key;
        } else if(!is_array($value)) {
            $result .= '<li>' . $value;
        }
        if(is_array($value)) {
            $result .= '<ul>';
            $result .= buildLists($value);
            $result .= '</ul>';
        } else {
            $result .= '</li>';
        }
    }
    return $result;
}

用法：

<nav>
   <ul>
       <?= buildLists($array); ?>
   </ul>
</nav>

输出：

<li>home</li>
<li>page 1
    <ul>
        <li>page 1.1
            <ul>
                <li>page 1.1.1</li>
                <li>page 1.1.2</li>
            </ul>
        </li>
        <li>page 1.2</li>
    </ul>
</li>
<li>page 2
    <ul>
        <li>page 2.1</li>
    </ul>
</li>