<"<tr>
  <td><input type='checkbox' name='list[\$id]' value='\$id'></td>
  <td>\$id</td>
  <td>\$spacer\$name</td>
  <td><a href='add.php";
$tree=new Tree();
$tree->init($tree_data);
echo "<table>";
echo $tree->get_tree(0, $str);
echo "</table>";
echo "<br/>";
echo "<br/>";
echo "<br/>";
echo "<br/>";
/**
 * 输出下拉列表
 */
$str="<option value=\$id \$selected>\$spacer\$name</option>";
$tree=new Tree();
$tree->init($tree_data);
echo "<select>";
echo $tree->get_tree(0, $str,2);
echo "</select>";

<" ";
  /**
  * @access private
  */
  public $ret = '';
  /**
  * 构造函数，初始化类
  * @param array 2维数组，例如：
  * array(
  *   1 => array('id'=>'1','parentid'=>0,'name'=>'一级栏目一'),
  *   2 => array('id'=>'2','parentid'=>0,'name'=>'一级栏目二'),
  *   3 => array('id'=>'3','parentid'=>1,'name'=>'二级栏目一'),
  *   4 => array('id'=>'4','parentid'=>1,'name'=>'二级栏目二'),
  *   5 => array('id'=>'5','parentid'=>2,'name'=>'二级栏目三'),
  *   6 => array('id'=>'6','parentid'=>3,'name'=>'三级栏目一'),
  *   7 => array('id'=>'7','parentid'=>3,'name'=>'三级栏目二')
  *   )
  */
  public function init($arr=array()){
    $this->arr = $arr;
    $this->ret = '';
    return is_array($arr);
  }
  /**
  * 得到父级数组
  * @param int
  * @return array
  */
  public function get_parent($myid){
    $newarr = array();
    if(!isset($this->arr[$myid])) return false;
    $pid = $this->arr[$myid]['parentid'];
    $pid = $this->arr[$pid]['parentid'];
    if(is_array($this->arr)){
      foreach($this->arr as $id => $a){
        if($a['parentid'] == $pid) $newarr[$id] = $a;
      }
    }
    return $newarr;
  }
  /**
  * 得到子级数组
  * @param int
  * @return array
  */
  public function get_child($myid){
    $a = $newarr = array();
    if(is_array($this->arr)){
      foreach($this->arr as $id => $a){
        if($a['parentid'] == $myid) $newarr[$id] = $a;
      }
    }
    return $newarr "<option value=\$id \$selected>\$spacer\$name</option>"
  * @param int 被选中的ID，比如在做树型下拉框的时候需要用到
  * @return string
  */
  public function get_tree($myid, $str, $sid = 0, $adds = '', $str_group = ''){
    $number=1;
    $child = $this->get_child($myid);
    if(is_array($child)){
      $total = count($child);
      foreach($child as $id=>$value){
        $j=$k='';
        if($number==$total){
          $j .= $this->icon[2];
        }else{
          $j .= $this->icon[1];
          $k = $adds "\$nstr = \"$str_group\";") : eval("\$nstr = \"$str\";");
        $this->ret .= $nstr;
        $nbsp = $this->nbsp;
        $this->get_tree($id, $str, $sid, $adds.$k.$nbsp,$str_group);
        $number++;
      }
    }
    return $this->ret;
  }
  /**
  * 同上一方法类似,但允许多选
  */
  public function get_tree_multi($myid, $str, $sid = 0, $adds = ''){
    $number=1;
    $child = $this->get_child($myid);
    if(is_array($child)){
      $total = count($child);
      foreach($child as $id=>$a){
        $j=$k='';
        if($number==$total){
          $j .= $this->icon[2];
        }else{
          $j .= $this->icon[1];
          $k = $adds "\$nstr = \"$str\";");
        $this->ret .= $nstr;
        $this->get_tree_multi($id, $str, $sid, $adds.$k.' ');
        $number++;
      }
    }
    return $this->ret;
  }
   /**
  * @param integer $myid 要查询的ID
  * @param string $str  第一种HTML代码方式
  * @param string $str2 第二种HTML代码方式
  * @param integer $sid 默认选中
  * @param integer $adds 前缀
  */
  public function get_tree_category($myid, $str, $str2, $sid = 0, $adds = ''){
    $number=1;
    $child = $this->get_child($myid);
    if(is_array($child)){
      $total = count($child);
      foreach($child as $id=>$a){
        $j=$k='';
        if($number==$total){
          $j .= $this->icon[2];
        }else{
          $j .= $this->icon[1];
          $k = $adds "\$nstr = \"$str\";");
        } else {
          eval("\$nstr = \"$str2\";");
        }
        $this->ret .= $nstr;
        $this->get_tree_category($id, $str, $str2, $sid, $adds.$k.' ');
        $number++;
      }
    }
    return $this->ret;
  }
  /**
   * 同上一类方法，jquery treeview 风格，可伸缩样式（需要treeview插件支持）
   * @param $myid 表示获得这个ID下的所有子级
   * @param $effected_id 需要生成treeview目录数的id
   * @param $str 末级样式
   * @param $str2 目录级别样式
   * @param $showlevel 直接显示层级数，其余为异步显示，0为全部限制
   * @param $style 目录样式 默认 filetree 可增加其他样式如'filetree treeview-famfamfam'
   * @param $currentlevel 计算当前层级，递归使用 适用改函数时不需要用该参数
   * @param $recursion 递归使用 外部调用时为FALSE
   */
  function get_treeview($myid,$effected_id='example',$str="<span class='file'>\$name</span>", $str2="<span class='folder'>\$name</span>" ,$showlevel = 0 ,$style='filetree ' , $currentlevel = 1,$recursion=FALSE) {
    $child = $this->get_child($myid);
    if(!defined('EFFECTED_INIT')){
      $effected = ' id="'.$effected_id.'"';
      define('EFFECTED_INIT', 1);
    } else {
      $effected = '';
    }
    $placeholder =   '<ul><li><span class="placeholder"></span></li></ul>';
    if(!$recursion) $this->str .='<ul'.$effected.' class="'.$style.'">';
    foreach($child as $id=>$a) {
      @extract($a);
      if($showlevel > 0 && $showlevel == $currentlevel && $this->get_child($id)) $folder = 'hasChildren'; //如设置显示层级模式@2011.07.01
      $floder_status = isset($folder) "'.$folder.'"' : '';
      $this->str .= $recursion "\$nstr = \"$str2\";");
        $this->str .= $nstr;
        if($showlevel == 0 || ($showlevel > 0 && $showlevel > $currentlevel)) {
          $this->get_treeview($id, $effected_id, $str, $str2, $showlevel, $style, $currentlevel+1, TRUE);
        } elseif($showlevel > 0 && $showlevel == $currentlevel) {
          $this->str .= $placeholder;
        }
      } else {
        eval("\$nstr = \"$str\";");
        $this->str .= $nstr;
      }
      $this->str .=$recursion "\$data[$n]['text'] = \"$str\";");
        } else {
          $data[$n]['text'] = iconv(CHARSET,'utf-8',$c['catname']);
        }
      }
      $n++;
    }
    return json_encode($data);
  }
  private function have($list,$item){
    return(strpos(',,'.$list.',',','.$item.','));
  }
}
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