XML「樹」，以多層次的HTML列表

Question

我有一個XML文件，我想將其顯示爲多級列表

<items> 
    <item> 
    <parent_id>1</parent_id> 
    <id>1876</id> 
    <name>foobar1</name> 
    </item> 
    <item> 
    <parent_id>1876</parent_id> 
    <id>1877</id> 
    <name>foobar11</name> 
    </item> 
    <item> 
    <parent_id>1877</parent_id> 
    <id>1878</id> 
    <name>foobar111</name> 
    </item> 
    <item> 
    <parent_id>1877</parent_id> 
    <id>1879</id> 
    <name>foobar112</name> 
    </item> 
    <item> 
    <parent_id>1877</parent_id> 
    <id>1880</id> 
    <name>foobar113</name> 
    </item> 
... 
</items> 

，我想其顯示如下：

<ul> 
    <li>foobar1</li> 
    <li> 
     <ul> 
     <li>foobar11</li> 
     <li> 
      <ul> 
      <li>foobar111</li> 
      <li>foobar112</li> 
      <li>foobar113</li> 
      </ul> 
     </li> 
     </ul> 
    </li> 
... 
</ul> 

我試圖做一個循環（我使用的SimpleXML）：

$catxml = simplexml_load_file('file.xml'); 
    $nodes=$catxml->xpath("//item");  
    $gile=0; 
    $ile=0; 

    foreach($nodes as $node) { 
     $par = $node->parent_id; 
     $id = $node->id; 
     $naz = $node->name; 

     if($par=='1'){ $gile++; $ile++; echo '<li><a href="#url">'.$id.'-'.$naz.'</a></li>'; 
     settype($id,'integer');   
      foreach($nodes as $nodea) { 
       $apar = $nodea->parent_id; 
       $aid = $nodea->id; 
       $anaz = $nodea->name; 
       settype($aid,'integer'); 
       $apoczatek=''; 
       if($apar!='1' AND $apar==$id AND $aid>$id){ $ile++; if($apoczatek!=''){echo '</ul></li>';}echo '<li><ul><li><a href="#url">'.$aid.'-'.$anaz.'</a></li>'; 
        foreach($nodes as $nodea) { 
         $bpar = $nodea->parent_id; 
         $bid = $nodea->id; 
         $bnaz = $nodea->name; 
         $bpoczatek=''; 
         settype($bid,'integer'); 
         if($bpar==$aid AND $bid>$aid){ $ile++; if($bpoczatek!=''){echo '</ul>';}echo '<ul><li><a href="#url">'.$bid.'-'.$bnaz.'</a></li>'; 
          foreach($nodes as $nodea) { 
           $cpar = $nodea->parent_id; 
           $cid = $nodea->id; 
           $cnaz = $nodea->name; 
           $cpoczatek=''; 
           settype($cid,'integer'); 
           if($cpar==$bid AND $cid>$bid){ $ile++; if($cpoczatek!=''){echo '</ul>';}echo '<ul><li><a href="#url">'.$cid.'-'.$cnaz.'</a></li>'; 
            foreach($nodes as $nodea) { 
             $dpar = $nodea->parent_id; 
             $did = $nodea->id; 
             $dnaz = $nodea->name; 
             $dpoczatek=''; 
             settype($did,'integer'); 
             if($dpar==$cid AND $did>$cid){ $ile++; if($dpoczatek!=''){echo '</ul>';}echo '<ul><li><a href="#url">'.$did.'-'.$dnaz.'</a></li>'; 
              foreach($nodes as $nodea) { 
               $epar = $nodea->parent_id; 
               $eid = $nodea->id; 
               $enaz = $nodea->name; 
               $epoczatek=''; 
               settype($eid,'integer'); 
               if($epar==$did AND $eid>$did){ $ile++; if($epoczatek!=''){echo '</ul>';}echo '<ul><li><a href="#url">'.$eid.'-'.$enaz.'</a></li>'; 

               } 
              } 
             } 
            } 
           } 
          } 
         } 
        } 
       } 
      } 
     } 
    } 

，但沒有奏效 - 錯過<ul>和</ul>標籤

對我的方法有任何建議嗎？有沒有其他方法可以做到這一點？

Answer 1

我對遞歸數據使用了遞歸函數。 另外我注意到了// echo "</li>\n<li>";：它是你想要的HTML結構所需要的，但我不喜歡它。

$catxml = simplexml_load_file('file.xml'); 
$nodes=$catxml->xpath("//item"); 

$children = array(); 

foreach($nodes as $node) { 
    $parent_id = (int) $node->parent_id; 
    if(! array_key_exists ($parent_id, $children)) { 
     $children[$parent_id] = array(); 
    } 
    $children[$parent_id][] = $node; 
} 

function renderChildrenList(&$children, $id) { 
    echo "\n<ul>"; 
    foreach($children[$id] as $node) { 
     echo "\n<li>" . $node->id . '-' . $node->name; 

     $child_id = (int) $node->id; 
     if(array_key_exists($child_id, $children)) { 
      // echo "</li>\n<li>"; 
      renderChildrenList($children, $child_id); 
     } 

     echo "</li>"; 
    } 
    echo "\n</ul>"; 
} 

// I assume root_id=1 
renderChildrenList($children, 1, 0);