通过PHP的CSS下拉菜单，逻辑打败了我

Question

今天早上我的大脑似乎不想工作..我有以下数组：

private $nav_pages = [['0', 'Home', 'home'],
                      ['0', 'About Us', 'about'],
                      ['0', 'Our Services', 'services'],
                      ['1', 'PROCURE TO PAY (P2P)', 'procure'],
                      ['1', 'ORDER TO CASH (02C)', 'cash'],
                      ['1', 'GENERAL ACCOUNTING', 'general'],
                      ['2', 'Charting of Accounts', 'charting'],
                      ['2', 'General Ledger Maintenance', 'maintenance'],
                      ['2', 'Accounts Receivable Services', 'receivable'],
                      ['2', 'Accounts Payable Services', 'payable'],
                      ['2', 'Reconciliation of Bank Accounts and Credit Cards', 'reconciliation'],
                      ['2', 'Preparing Financial Statements', 'statements'],
                      ['2', 'Payroll Processing', 'payroll'],
                      ['1', 'CLOSING & REPORTING', 'closing'],
                      ['0', 'How It Works', 'how-it-works'],
                      ['0', 'Contact Us','contact'],
                      ['0', 'Careers', 'careers']];

然后将其馈送到一个 php 页面，该页面旨在布置一个多层纯 css 下拉菜单.. php 页面代码是：

<ul class="<?php echo $ul_class; ?>">

<?php $this_layer = 0;

// place array content into variables
foreach ($links as $link) {

    $item_layer  = $link[0];
    $item_string = $link[1];
    $item_link   = $link[2];

    if ($item_layer > $this_layer) { ?>
        <ul>
    <?php $this_layer++; }
    elseif ($item_layer == $this_layer) { ?>
        <li class="<?php echo $item_link; ?>">
            <a class="<?php echo $item_link; ?>"
               href="/<?php echo $item_link; ?>">
                <?php echo $item_string; ?>
            </a>
        </li>
    <?php }
    elseif ($item_layer < $this_layer) { ?>
        </li></ul>
    <?php $this_layer--; } ?>
<?php } ?>

输出不正确，因为上面的代码总是在第二层准备好关闭之前关闭包含第二层的列表项。如果这有意义..

<ul class="pages_nav">
<li class="home">
    <a class="home"
       href="/home">
        Home                
    </a>
</li>
<li class="about">
    <a class="about"
       href="/about">
        About Us                
    </a>
</li>
<li class="services">
    <a class="services"
       href="/services">
        Our Services                
    </a>
</li>
<ul>
    <li class="cash">
        <a class="cash"
           href="/cash">
            ORDER TO CASH (02C)                
        </a>
    </li>
    <li class="general">
        <a class="general"
           href="/general">
            GENERAL ACCOUNTING                
        </a>
    </li>
    <ul>
        <li class="maintenance">
            <a class="maintenance"
               href="/maintenance">
                General Ledger Maintenance                
            </a>
        </li>
        <li class="receivable">
            <a class="receivable"
               href="/receivable">
                Accounts Receivable Services                
            </a>
        </li>
        <li class="payable">
            <a class="payable"
               href="/payable">
                Accounts Payable Services                
            </a>
        </li>
        <li class="reconciliation">
            <a class="reconciliation"
               href="/reconciliation">
                Reconciliation of Bank Accounts and Credit Cards                
            </a>
        </li>
        <li class="statements">
            <a class="statements"
               href="/statements">
                Preparing Financial Statements               
            </a>
        </li>
        <li class="payroll">
            <a class="payroll"
               href="/payroll">
                Payroll Processing                
            </a>
        </li>
        </li></ul>
    </li></ul>
<li class="contact">
    <a class="contact"
       href="/contact">
        Contact Us                
    </a>
</li>
<li class="careers">
    <a class="careers"
       href="/careers">
        Careers                
    </a>
</li>

解决方案：

<ul class="<?php echo $ul_class; ?>">

<?php $this_layer = 0;

// place array content into variables
foreach ($links as $link) {

    $item_layer  = $link[0];
    $item_string = $link[1];
    $item_link   = $link[2];

    // check if link needs to be manipulated
    switch($do) {
        case 'strtolower':
            $item_string = strtolower($item_string);
            break;
        case 'strtoupper':
            $item_string = strtoupper($item_string);
            break;
    } ?>

    <?php if ($item_layer > $this_layer) { ?>
        <ul>
        <li class="<?php echo $item_link; ?>">
            <a class="<?php echo $item_link; ?>"
               href="/<?php echo $item_link; ?>">
                <?php echo $item_string; ?>
            </a>
    <?php $this_layer++; }
    elseif ($item_layer == $this_layer) { ?>
        </li><li class="<?php echo $item_link; ?>">
            <a class="<?php echo $item_link; ?>"
               href="/<?php echo $item_link; ?>">
                <?php echo $item_string; ?>
            </a>
    <?php }
    elseif ($item_layer < $this_layer) { ?>
        </li></ul></li><li class="<?php echo $item_link; ?>">
        <a class="<?php echo $item_link; ?>"
           href="/<?php echo $item_link; ?>">
            <?php echo $item_string; ?>
        </a>
        <?php $this_layer--; } ?>
<?php } ?>

Answer 1

永远不要关闭li标签，添加东西时关闭它

foreach ($links as $link) {
    if ($item_layer > $this_layer) { 
        echo '<ul><li> ......';
        this_layer++; 
    }elseif ($item_layer == $this_layer) {
        echo '</li><li>......';
    }elseif ($item_layer < $this_layer) {
        echo '</li></ul><li>......';
        $this_layer--; 
    }
}

最后你可能需要在 foreach 之外添加一个echo '</li></ul>' 以关闭所有内容

Answer 2

不得不对代码进行一些修改，通常我将 php 菜单结构组织成树形结构，这样更容易解析成 html 菜单，但这里是：

<ul class="<?php echo $ul_class; ?>">
<?php 
$this_layer = 0;
$closeit = false;
// place array content into variables
foreach ($nav_pages as $link) {
    $item_layer  = $link[0];
    $item_string = $link[1];
    $item_link   = $link[2];

    if ($item_layer > $this_layer) { 
      // Changing level, dont close the previous li
      ?><ul><?php 
      $closeit = false;
      $this_layer++; 
    }
    if ($item_layer == $this_layer) { 
      // Same level, check if you need to close previous li
      if ($closeit) {
        ?></li><?php
      }
      // Render the li
    ?>
  <li class="<?php echo $item_link; ?>">
    <a class="<?php echo $item_link; ?>"
        href="/<?php echo $item_link; ?>">
      <?php echo $item_string; ?>
    </a>
    <?php 
      // Close it on next loop
      $closeit = true;
    }
    elseif ($item_layer < $this_layer) { 
      // Changing layer back down, close the previous li and the current level ul
      ?>
  </li>
</ul>
    <?php
      $this_layer--; 
    } 
} 
// Finished loop, there should still be a li waiting to be closed
if ($closeit) { 
  ?></li><?php 
}
// Close menu
?>
</ul>

应该可以了，如果不行请告诉我

建议的php菜单结构：

$menu = array(
    array(
        "url"=>"/place.php",
        "text"=>"Go to place"
    ),
    array(
        "url"=>"/place2.php", // not necessary
        "text"=>"with submenu",
        "children"=>array(
            array(
                "url"=>"/placewithinplace2.php",
                "text"=>"submenu item"
            )
        )
    )
);