PHP实现简单的模板引擎功能示例

<?php
namespace foo\base;
use foo\base\Object;
use foo\base\Compiler;
/**
* 
*/
class Template extends Object
{
  private $_config = [
    'suffix' => '.php',//文件后缀名
    'templateDir' => '../views/',//模板所在文件夹
    'compileDir' => '../runtime/cache/views/',//编译后存放的目录
    'suffixCompile' => '.php',//编译后文件后缀
    'isReCacheHtml' => false,//是否需要重新编译成静态html文件
    'isSupportPhp' => true,//是否支持php的语法
    'cacheTime' => 0,//缓存时间,单位秒
  ];
  private $_file;//带编译模板文件
  private $_valueMap = [];//键值对
  private $_compiler;//编译器
  public function __construct($compiler, $config = [])
  {
    $this->_compiler = $compiler;
    $this->_config = array_merge($this->_config, $config);
  }
  /**
   * [assign 存储控制器分配的键值]
   * @param [type] $values [键值对集合]
   * @return [type]     [description]
   */
  public function assign($values)
  {
    if (is_array($values)) {
      $this->_valueMap = $values;
    } else {
      throw new \Exception('控制器分配给视图的值必须为数组!');
    }
    return $this;
  }
  /**
   * [show 展现视图]
   * @param [type] $file [带编译缓存的文件]
   * @return [type]    [description]
   */
  public function show($file)
  {
    $this->_file = $file;
    if (!is_file($this->path())) {
      throw new \Exception('模板文件'. $file . '不存在!');
    }
    $compileFile = $this->_config['compileDir'] . md5($file) . $this->_config['suffixCompile'];
    $cacheFile = $this->_config['compileDir'] . md5($file) . '.html';
    //编译后文件不存在或者缓存时间已到期,重新编译,重新生成html静态缓存
    if (!is_file($compileFile) || $this->isRecompile($compileFile)) {
      $this->_compiler->compile($this->path(), $compileFile, $this->_valueMap);
      $this->_config['isReCacheHtml'] = true;
      if ($this->isSupportPhp()) {
        extract($this->_valueMap, EXTR_OVERWRITE);//从数组中将变量导入到当前的符号表
      }
    }
    if ($this->isReCacheHtml()) {
      ob_start();
      ob_clean();
      include($compileFile);
      file_put_contents($cacheFile, ob_get_contents());
      ob_end_flush();
    } else {
      readfile($cacheFile);
    }
  }
  /**
   * [isRecompile 根据缓存时间判断是否需要重新编译]
   * @param [type] $compileFile [编译后的文件]
   * @return boolean       [description]
   */
  private function isRecompile($compileFile)
  {
    return time() - filemtime($compileFile) > $this->_config['cacheTime'];
  }
  /**
   * [isReCacheHtml 是否需要重新缓存静态html文件]
   * @return boolean [description]
   */
  private function isReCacheHtml()
  {
    return $this->_config['isReCacheHtml'];
  }
  /**
   * [isSupportPhp 是否支持php语法]
   * @return boolean [description]
   */
  private function isSupportPhp()
  {
    return $this->_config['isSupportPhp'];
  }
  /**
   * [path 获得模板文件路径]
   * @return [type] [description]
   */
  private function path()
  {
    return $this->_config['templateDir'] . $this->_file . $this->_config['suffix'];
  }
}

<?php
namespace foo\base;
use foo\base\Object;
/**
* 
*/
class Compiler extends Object
{
  private $_content;
  private $_valueMap = [];
  private $_patten = [
    '#\{\\$([a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*)\}#',
    '#\{if (.*?)\}#',
    '#\{(else if|elseif) (.*?)\}#',
    '#\{else\}#',
    '#\{foreach \\$([a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*)}#',
    '#\{\/(foreach|if)}#',
    '#\{\\^(k|v)\}#',
  ];
  private $_translation = [
    "<?php echo \$this->_valueMap['\\1']; ?>",
    '<?php if (\\1) {?>',
    '<?php } else if (\\2) {?>',
    '<?php }else {?>',
    "<?php foreach (\$this->_valueMap['\\1'] as \$k => \$v) {?>",
    '<?php }?>',
    '<?php echo \$\\1?>'
  ];
  /**
   * [compile 编译模板文件]
   * @param [type] $source  [模板文件]
   * @param [type] $destFile [编译后文件]
   * @param [type] $values  [键值对]
   * @return [type]      [description]
   */
  public function compile($source, $destFile, $values)
  {
    $this->_content = file_get_contents($source);
    $this->_valueMap = $values;
    if (strpos($this->_content, '{$') !== false) {
      $this->_content = preg_replace($this->_patten, $this->_translation, $this->_content);
    }
    file_put_contents($destFile, $this->_content);
  }
}