一个PHP模板,主要想体现一下思路

$tpl = new Template($tpl_prefix);

$cats = array(
    array('forum_id'=>'1','forum_cat_id'=>'0','forum_name'=>'PHP学习'),
   array('forum_id'=>'2','forum_cat_id'=>'0','forum_name'=>'MYSQL学习')
);
$forums = array(
   array('forum_id'=>'3','forum_cat_id'=>'1','forum_name'=>'PHP高级教程'),
   array('forum_id'=>'4','forum_cat_id'=>'1','forum_name'=>'PHP初级教程'),
   array('forum_id'=>'5','forum_cat_id'=>'2','forum_name'=>'MYSQL相关资料')
);

if ($cats)
{
   if ($tpl->chk_cache($tpl_index))//检查判断是否需要重新生产PHP模板文件.
    {
       $tpl->load_tpl($tpl_index);//加载html模板文件.
      //替换PHP语句
      $tpl->assign_block("{block_cat}","<?foreach(\$cats as \$cat) {?>");
      $tpl->assign_block("{/block_cat}","<?}?>");
        $tpl->assign_block("{block_forum}","<?foreach(\$forums as \$forum) {

\nif(\$forum['forum_cat_id'] == \$cat['forum_id']) {?>");
       $tpl->assign_block("{/block_forum}","<?}\n}?>");
      //生产PHP模板文件.
      $tpl->write_cache($tpl_index);
   }
}
//包含PHP模板文件.
include($tpl->parse_tpl($tpl_index));
?>

//$this->$template,储存模板数据.
   var $template = '';

//模板路径.
   var $tpl_path = '';

//模板前缀(风格名称).
   var $tpl_prefix = '';

//cache路径(编译后的路径).
   var $cache_path = '';

//css文件路径.
   var $css_path = '';

//header文件路径.
   var $header_path = '';

//footer文件路径
    var $footer_path = '';

/**
   * 初始化模板路径.
   */
   function Template($root = 'default')
   {
      //模板前缀(风格名称).
      $this->tpl_prefix = $root;
      //模板文件路径.
      $this->tpl_path = './templates/' . $root . '/';
      //生成的PHP文件存放路径.
      $this->cache_path = './template_data/' .$this->tpl_prefix . '_';
      return true;
   }

/**
   * chk_cache,检查"编译"后的模板是否需要更新,判断依据:最后修改时间,"编译"文件是否存在.
   */
   function chk_cache($tpl_index)
    {
      $tpl_file = $this->tpl_path . $tpl_index . '.html';
      $cache_file = $this->cache_path . $tpl_index . '.php';
      //判断是否需要更新.
      if(!file_exists($cache_file))
        {
         return true;
      }
        elseif(filemtime($tpl_file) > filemtime($cache_file))
        {
         return true;
      }
   }

/**
   * 输出模板文件.
   */
   function parse_tpl($tpl_index,$message='')
    {
       return $this->cache_path . $tpl_index . '.php';
    }

/**
   * 加载模板文件.
   */
   function load_tpl($tpl_index)
    {
      $tpl_file = $this->tpl_path . $tpl_index . '.html';
      $fp = fopen($tpl_file, 'r');
      $this->template = fread($fp, filesize($tpl_file));
      fclose($fp);
   }

/**
   * 替换变量,并且"编译"模板.
   */
   function write_cache($tpl_index)
    {

$cache_file = $this->cache_path . $tpl_index . '.php';

//变量显示.
      $this->template = preg_replace("/(\{=)(.+?)(\})/is", "<?=\\2?>", $this->template);

//界面语言替换.
      $this->template = preg_replace("/\{lang +(.+?)\}/ies", "\$lang['main']['\\1']", $this->template);

$fp = fopen($cache_file, 'w');
        flock($fp, 3);
        fwrite($fp, $this->template);
        fclose($fp);
    }

/**
   * 替换block.
   */
   function assign_block($search,$replace)
    {
      $this->template = str_replace($search,$replace,$this->template);
   }
}
?>