解析thinkPHP基于反射实现钩子的方法

<?php
class BlogAction {
  public function detail() {
    echo 'detail' . "
";
  }
  public function test($year = 2014, $month = 4, $day = 21) {
    echo $year . '--' . $month . '--' . $day . "
";
  }
  public function _before_detail() {
    echo __FUNCTION__ . "
";
  }
  public function _after_detail() {
    echo __FUNCTION__ . "
";
  }
}
// 执行detail方法
$method = new ReflectionMethod('BlogAction', 'detail');
$instance = new BlogAction();
// 进行权限判断
if ($method->isPublic()) {
  $class = new ReflectionClass('BlogAction');
  // 执行前置方法
  if ($class->hasMethod('_before_detail')) {
    $beforeMethod = $class->getMethod('_before_detail');
    if ($beforeMethod->isPublic()) {
      $beforeMethod->invoke($instance);
    }
  }
  $method->invoke(new BlogAction);
  // 执行后置方法
  if ($class->hasMethod('_after_detail')) {
    $beforeMethod = $class->getMethod('_after_detail');
    if ($beforeMethod->isPublic()) {
      $beforeMethod->invoke($instance);
    }
  }
}
// 执行带参数的方法
$method = new ReflectionMethod('BlogAction', 'test');
$params = $method->getParameters();
foreach ($params as $param) {
  $paramName = $param->getName();
  if (isset($_REQUEST[$paramName])) {
    $args[] = $_REQUEST[$paramName];
  } elseif ($param->isDefaultValueAvailable()) {
    $args[] = $param->getDefaultValue();
  }
}
if (count($args) == $method->getNumberOfParameters()) {
  $method->invokeArgs($instance, $args);
} else {
  echo 'parameters is wrong!';
}

/**
 * 执行App控制器
 */
public function execApp() {
  // 创建action控制器实例
  $className = MODULE_NAME . 'Controller';
  $namespaceClassName = '\apps\' . APP_NAME . '\controller\' . $className;
  load_class($namespaceClassName, false);
  if (!class_exists($namespaceClassName)) {
    throw new Exception('Oops! Module not found : ' . $namespaceClassName);
  }
  $controller = new $namespaceClassName();
  // 获取当前操作名
  $action = ACTION_NAME;
  // 执行当前操作
  //call_user_func(array(&$controller, $action)); // 其实吧，用这个函数足够啦！！！
  try {
    $methodInfo = new ReflectionMethod($namespaceClassName, $action);
    if ($methodInfo->isPublic() && !$methodInfo->isStatic()) {
      $methodInfo->invoke($controller);
    } else { // 操作方法不是public类型，抛出异常
      throw new ReflectionException();
    }
  } catch (ReflectionException $e) {
    // 方法调用发生异常后，引导到__call方法处理
    $methodInfo = new ReflectionMethod($namespaceClassName, '__call');
    $methodInfo->invokeArgs($controller, array($action, ''));
  }
  return;
}