写一个MVC的模板解析方法

MVC是模型(Model)、视图(View)和控制(Controller)的缩写，PHP中采用MVC模式的目的是实现Web系统的职能分工，通俗的说就是把业务逻辑处理从用户界面视图中分离出来。使Web系统的开发与维护更加方便，从而有效的节省人力物力，受到了越来越多企业的青睐。

模板引擎是MVC模式建立过程的重要方法，开发者可以设计一套赋予含义的标签，通过技术解析处理有效的把数据逻辑处理从界面模板中提取出来，通过解读标签的含义把控制权提交给相应业务逻辑处理程序，从而获取到需要的数据，以模板设计的形式展现出来，使设计人员能把精力更多放在表现形式上。下面是我对模板引擎的认识与设计方法：

说的好听些叫模板引擎，实际就是解读模板数据的过程（个人观点^^）。通过我对建站方面的思考认识，网站在展现形式上无非归纳为单条和多条两种形式，那么我们可以设定两种对应标签（如data、list）来处理这两种情况，关键点在于解决两种标签的多层相互嵌套问题，基本适合实现80%界面形式。

解读模板的方法有多种，常用的包括字符串处理（解决嵌套稍麻烦）、正则表达式。在这里我选用的正则表达式，下面是我的处理方法（本文仅提供思路和参考代码，可能不能直接使用）。

模板文件解析类：

<?php
       class Template {
             public $html, $vars, $bTag, $eTag;
             public $bFlag='{', $eFlag='}', $pfix='zmm:';
             private $folder, $file;
             function __construct($vars=array()) {
                 !empty($vars) && $this->vars = $vars;
                 !empty($GLOBALS['cfg_tag_prefix']) && 
                 $this->pfix = $GLOBALS['cfg_tag_prefix'].':';
                 $this->bTag = $this->bFlag.$this->pfix;
                 $this->eTag = $this->bFlag.'\/'.$this->pfix;
                 empty(Tags::$vars) && Tags::$vars = &$this->vars;
             }
             public function LoadTpl($tpl) {
                 $this->file = $this->GetTplPath($tpl);
                 Tags::$file = &$this->file;
                 if (is_file($this->file)) {
                     if ($this->GetTplHtml()) {
                         $this->SetTplTags();
                     } else {
                         exit('模板文件加载失败！');
                     }
                 } else {
                     exit('模板文件['.$this->file.']不存在！');
                 }
             }
             private function GetTplPath($tpl) {
                 $this->folder = WEBSITE_DIRROOT.
                                 $GLOBALS['cfg_tpl_root'];
                 return $this->folder.'/'.$tpl;
             }
             private function GetTplHtml() {
                 $html = self::FmtTplHtml(file_get_contents($this->file)); 
                 if (!empty($html)) {
                     $callFunc = Tags::$prefix.'Syntax'; 
                     $this->html = Tags::$callFunc($html, new Template());
                 } else {
                     exit('模板文件内容为空！');
                 } return true;
             }
             static public function FmtTplHtml($html) {
                 return preg_replace('/(\r)|(\n)|(\t)|(\s{2,})/is', '', $html);
             }
             public function Register($vars=array()) {
                 if (is_array($vars)) {
                     $this->vars = $vars;
                     Tags::$vars = &$this->vars;
                 }
             }
             public function Display($bool=false, $name="", $time=0) {
                 if (!empty($this->html)) { 
                     if ($bool && !empty($name)) {
                         if (!is_int($time)) $time = 600;
                         $cache = new Cache($time);
                         $cache->Set($name, $this->html);
                     } 
                     echo $this->html; flush();
                 } else {
                     exit('模板文件内容为空！');
                 }
             }
             public function SetAssign($souc, $info) {
                 if (!empty($this->html)) {
                     $this->html = str_ireplace($souc, self::FmtTplHtml($info), $this->html);
                 } else {
                     exit('模板文件内容为空！');
                 }
             } 
             private function SetTplTags() {
                 $this->SetPanelTags(); $this->SetTrunkTags(); $this->RegHatchVars();
             }
             private function SetPanelTags() {
                 $rule = $this->bTag.'([^'.$this->eFlag.']+)\/'.$this->eFlag;
                 preg_match_all('/'.$rule.'/ism', $this->html, $out_matches);
                 $this->TransTag($out_matches, 'panel'); unset($out_matches);
             }
             private function SetTrunkTags() {
                 $rule = $this->bTag.'(\w+)\s*([^'.$this->eFlag.']*?)'.$this->eFlag.
                         '((?:(?!'.$this->bTag.')[\S\s]*?|(?R))*)'.$this->eTag.'\\1\s*'.$this->eFlag;
                 preg_match_all('/'.$rule.'/ism', $this->html, $out_matches);
                 $this->TransTag($out_matches, 'trunk'); unset($out_matches);
             }
             private function TransTag($result, $type) {
                 if (!empty($result[0])) {
                     switch ($type) {
                         case 'panel' : {
                              for ($i = 0; $i < count($result[0]); $i ++) {
                                   $strTag = explode(' ', $result[1][$i], 2);
                                   if (strpos($strTag[0], '.')) {
                                       $itemArg = explode('.', $result[1][$i], 2);
                                       $callFunc = Tags::$prefix.ucfirst($itemArg[0]);
                                       if (method_exists('Tags', $callFunc)) {
                                           $html = Tags::$callFunc(chop($itemArg[1]));
                                           if ($html !== false) {
                                               $this->html = str_ireplace($result[0][$i], $html, $this->html);
                                           }
                                       }
                                   } else {
                                       $rule = '^([^\s]+)\s*([\S\s]+)$';
                                       preg_match_all('/'.$rule.'/is', trim($result[1][$i]), $tmp_matches);
                                       $callFunc = Tags::$prefix.ucfirst($tmp_matches[1][0]);
                                       if (method_exists('Tags', $callFunc)) {
                                           $html = Tags::$callFunc($tmp_matches[2][0]);
                                           if ($html !== false) {
                                               $this->html = str_ireplace($result[0][$i], $html, $this->html);
                                           }
                                       } unset($tmp_matches);
                                   }
                              } break;
                         }
                         case 'trunk' : {
                              for ($i = 0; $i < count($result[0]); $i ++) {
                                   $callFunc = Tags::$prefix.ucfirst($result[1][$i]);
                                   if (method_exists('Tags', $callFunc)) {
                                       $html = Tags::$callFunc($result[2][$i], $result[3][$i]);
                                       $this->html = str_ireplace($result[0][$i], $html, $this->html);
                                   }
                              } break;
                         }
                         default: break;  
                     }
                 } else {
                     return false;
                 }
             }
             private function RegHatchVars() {
                 $this->SetPanelTags();
             }
             function __destruct() {}
       }
?>

标签解析类：（目前暂时提供data、list两种标签的解析，说明思路）

<?php
       class Tags {
             static private $attrs=null;
             static public  $file, $vars, $rule, $prefix='TAG_';
             static public function TAG_Syntax($html, $that) {                
                 $rule = $that->bTag.'if\s+([^'.$that->eFlag.']+)\s*'.$that->eFlag;
                 $html = preg_replace('/'.$rule.'/ism', '<?php if (\\1) { ?>', $html);
                 $rule = $that->bTag.'elseif\s+([^'.$that->eFlag.']+)\s*'.$that->eFlag;
                 $html = preg_replace('/'.$rule.'/ism', '<?php } elseif (\\1) { ?>', $html);
                 $rule = $that->bTag.'else\s*'.$that->eFlag;
                 $html = preg_replace('/'.$rule.'/ism', '<?php } else { ?>', $html);
                 $rule = $that->bTag.'loop\s+(\S+)\s+(\S+)\s*'.$that->eFlag;
                 $html = preg_replace('/'.$rule.'/ism', '<?php foreach (\\1 as \\2) { ?>', $html);
                 $rule = $that->bTag.'loop\s+(\S+)\s+(\S+)\s+(\S+)\s*'.$that->eFlag;
                 $html = preg_replace('/'.$rule.'/ism', '<?php foreach (\\1 as \\2 => \\3) { ?>', $html);
                 $rule = $that->eTag.'(if|loop)\s*'.$that->eFlag;
                 $html = preg_replace('/'.$rule.'/ism', '<?php } ?>', $html);
                 $rule = $that->bTag.'php\s*'.$that->eFlag.'((?:(?!'.
                         $that->bTag.')[\S\s]*?|(?R))*)'.$that->eTag.'php\s*'.$that->eFlag;
                 $html = preg_replace('/'.$rule.'/ism', '<?php \\1 ?>', $html);
                 return self::TAG_Execute($html);
             }
             static public function TAG_List($attr, $html) {
                 if (!empty($html)) {
                     if (self::TAG_HaveTag($html)) {
                         return self::TAG_DealTag($attr, $html, true);
                     } else {
                         return self::TAG_GetData($attr, $html, true);
                    }
                 } else {
                    exit('标签{list}的内容为空！');
                 } 
             }
             static public function TAG_Data($attr, $html) {
                 if (!empty($html)) {
                     if (self::TAG_HaveTag($html)) {
                         return self::TAG_DealTag($attr, $html, false);
                     } else {
                         return self::TAG_GetData($attr, $html, false);
                     }
                 } else {
                     exit('标签{data}的内容为空！');
                 } 
             }
             static public function TAG_Execute($html) {
                 ob_clean(); ob_start();
                 if (!empty(self::$vars)) {
                     is_array(self::$vars) && 
                     extract(self::$vars, EXTR_OVERWRITE);
                 } 
                 $file_inc = WEBSITE_DIRINC.'/buffer/'.
                             md5(uniqid(rand(), true)).'.php';
                 if ($fp = fopen($file_inc, 'xb')) {
                     fwrite($fp, $html); 
                     if (fclose($fp)) {
                         include($file_inc); 
                         $html = ob_get_contents(); 
                     } unset($fp);
                 } else {
                     exit('模板解析文件生成失败！');
                 } ob_end_clean(); @unlink($file_inc);
                 return $html;
             }
             static private function TAG_HaveTag($html) {
                 $bool_has = false; 
                 $tpl_ins = new Template();
                 self::$rule = $tpl_ins->bTag.'([^'.$tpl_ins->eFlag.']+)\/'.$tpl_ins->eFlag;
                 $bool_has = $bool_has || preg_match('/'.self::$rule.'/ism', $html);
                 self::$rule = $tpl_ins->bTag.'(\w+)\s*([^'.$tpl_ins->eFlag.']*?)'.$tpl_ins->eFlag.
                               '((?:(?!'.$tpl_ins->bTag.')[\S\s]*?|(?R))*)'.$tpl_ins->eTag.'\\1\s*'.$tpl_ins->eFlag;
                 $bool_has = $bool_has || preg_match('/'.self::$rule.'/ism', $html);
                 unset($tpl_ins);
                 return $bool_has;
             }
             static private function TAG_DealTag($attr, $html, $list) {
                 preg_match_all('/'.self::$rule.'/ism', $html, $out_matches);
                 if (!empty($out_matches[0])) {
                     $child_node = array();
                     for ($i = 0; $i < count($out_matches[0]); $i ++) {
                          $child_node[] = $out_matches[3][$i];
                          $html = str_ireplace($out_matches[3][$i], '{-->>child_node_'.$i.'<<--}', $html);
                     }
                     $html = self::TAG_GetData($attr, $html, $list);
                     for ($i = 0; $i < count($out_matches[0]); $i ++) {
                          $html = str_ireplace('{-->>child_node_'.$i.'<<--}', $child_node[$i], $html);
                     }
                     preg_match_all('/'.self::$rule.'/ism', $html, $tmp_matches);
                     if (!empty($tmp_matches[0])) {
                         for ($i = 0; $i < count($tmp_matches[0]); $i ++) {
                              $callFunc = self::$prefix.ucfirst($tmp_matches[1][$i]);
                              if (method_exists('Tags', $callFunc)) {
                                  $temp = self::$callFunc($tmp_matches[2][$i], $tmp_matches[3][$i]);
                                  $html = str_ireplace($tmp_matches[0][$i], $temp, $html);
                              }
                         }
                     } 
                     unset($tmp_matches);
                  }
                  unset($out_matches); return $html;
             } 
             static private function TAG_GetData($attr, $html, $list=false) {
                 if (!empty($attr)) {
                     $attr_ins = new Attbt($attr);
                     $attr_arr = $attr_ins->attrs;
                     if (is_array($attr_arr)) {
                         extract($attr_arr, EXTR_OVERWRITE);
                         $source = table_name($source, $column);
                         $rule = '\[field:\s*(\w+)\s*([^\]]*?)\s*\/?]';
                         preg_match_all('/'.$rule.'/is', $html, $out_matches);
                         $data_str = ''; 
                         $data_ins = new DataSql();
                         $attr_where = $attr_order = '';
                         if (!empty($where)) {
                             $where = str_replace(',', ' and ', $where);
                             $attr_where = ' where '. $where;
                         }
                         if (!empty($order)) {
                             $attr_order = ' order by '.$order;
                         } else {
                             $fed_name = '';
                             $fed_ins = $data_ins->GetFedNeedle($source);
                             $fed_cnt = $data_ins->GetFedCount($fed_ins);
                             for ($i = 0; $i < $fed_cnt; $i ++) {
                                  $fed_flag = $data_ins->GetFedFlag($fed_ins, $i);
                                  if (preg_match('/auto_increment/ism', $fed_flag)) {
                                      $fed_name = $data_ins->GetFedName($fed_ins, $i);
                                      break;
                                  }
                             }
                             if (!empty($fed_name)) 
                                 $attr_order = ' order by '.$fed_name.' desc';
                         }
                         if ($list == true) {
                             if (empty($source) && empty($sql)) {
                                 exit('标签{list}必须指定source属性！');
                             }
                             $attr_rows = $attr_page = '';
                             if ($rows > 0) {
                                 $attr_rows = ' limit 0,'.$rows;
                             }
                             if (!empty($sql)) {
                                 $data_sql = $sql;
                             } else {
                                 $data_sql = 'select * from `'.$source.'`'.
                                             $attr_where.$attr_order.$attr_rows;
                             }
                             if ($pages=='true' && !empty($size)) {
                                 $data_num = $data_ins->GetRecNum($data_sql);
                                 $page_cnt = ceil($data_num / $size);
                                 global $page;
                                 if (!isset($page) || $page < 1) $page = 1;                                 
                                 if ($page > $page_cnt) $page = $page_cnt;
                                 $data_sql = 'select * from `'.$source.'`'.$attr_where.
                                             $attr_order.' limit '.($page-1) * $size.','.$size;
                                 $GLOBALS['cfg_page_curr'] = $page;
                                 $GLOBALS['cfg_page_prev'] = $page - 1;
                                 $GLOBALS['cfg_page_next'] = $page + 1;
                                 $GLOBALS['cfg_page_nums'] = $page_cnt;
                                 if (function_exists('list_pagelink')) {
                                     $GLOBALS['cfg_page_list'] = list_pagelink($page, $page_cnt, 2);
                                 }
                             }
                             $data_idx = 0;
                             $data_ret = $data_ins->SqlCmdExec($data_sql);
                             while ($row = $data_ins->GetRecArr($data_ret)) {
                                    if ($skip > 0 && !empty($flag)) {
                                        $data_idx != 0 && 
                                        $data_idx % $skip == 0 && 
                                        $data_str .= $flag; 
                                    }
                                    $data_tmp = $html;
                                    $data_tmp = str_ireplace('@idx', $data_idx, $data_tmp);
                                    for ($i = 0; $i < count($out_matches[0]); $i ++) {
                                         $data_tmp = str_ireplace($out_matches[0][$i], 
                                                     $row[$out_matches[1][$i]], $data_tmp);
                                    }
                                    $data_str .= $data_tmp; $data_idx ++;                           
                             }
                         } else {
                             if (empty($source)) {
                                 exit('标签{data}必须指定source属性！');
                             }   
                             
                             $data_sql = 'select * from `'.$source.
                                         '`'.$attr_where.$attr_order;
                             $row = $data_ins->GetOneRec($data_sql);
                             if (is_array($row)) {
                                 $data_tmp = $html;
                                 for ($i = 0; $i < count($out_matches[0]); $i ++) {
                                      $data_val = $row[$out_matches[1][$i]];
                                      if (empty($out_matches[2][$i])) {
                                          $data_tmp = str_ireplace($out_matches[0][$i], $data_val, $data_tmp);
                                      } else {
                                          $attr_str = $out_matches[2][$i];
                                          $attr_ins = new Attbt($attr_str);
                                          $func_txt = $attr_ins->attrs['function'];
                                          if (!empty($func_txt)) {
                                              $func_tmp = explode('(', $func_txt);
                                              if (function_exists($func_tmp[0])) {
                                                  eval('$func_ret ='.str_ireplace('@me', 
                                                       '\''.$data_val.'\'', $func_txt)); 
                                                  $data_tmp = str_ireplace($out_matches[0][$i], $func_ret, $data_tmp);
                                              } else {
                                                  exit('调用了不存在的函数！');
                                              }
                                          } else {
                                              exit('标签设置属性无效！');
                                          }
                                      }
                                 }
                                 $data_str .= $data_tmp;
                             }
                         }
                         unset($data_ins);
                         return $data_str;
                     } else {
                         exit('标签设置属性无效！');
                     }
                 } else {
                     exit('没有设置标签属性！');
                 }
             }
             static public function __callStatic($name, $args) {
                 exit('标签{'.$name.'}不存在！');
             }
       }
?>