Continue not going to loop start

I am having a bit of trouble understanding this bug. Here is the code:

 function filter_optionsfordash(array $data,$dash) {
    $filtered_options = array();
    $len = strlen($dash);    
    foreach ($data as $k => $value) {
      if (substr($k,0,$len) === $dash) {
        $option_name = trim(str_replace($dash . '_','',$k)); 

        switch ($option_name) {
          case 'displayColumns':
            $value = explode(',',$value);
          break;

          case 'dashletTitle':
            $option_name = 'title';
          break;

          case 'id':
          case 'module':
          case 'action':
          case 'configure':
          case 'to_pdf':
            continue;
          break;
        }


        $filtered_options[$option_name] = $value;         
      }
    }    

    return $filtered_options;
  }

What I am trying to do here is to filter some values from the give array (in this case it will be the $_POST) which start with the given name ($dash), but I want to filter out the ones that are 'id', 'module', 'action', 'configure' or 'to_pdf'.

So what I thought would work is a 'continue'. Since the switch statement isn't a loop, 'continue' should go to the start of the loop (the foreach), but apparently this doesn't happen. I am still getting the key names I don't want in the array.

I have found a solution, by changing the code a bit, but I would reall开发者_如何学Goy like to understand why this doesn't work.

The 'continue' should send me back to the foreach!!

http://docs.php.net/continue says:

continue is used within looping structures to skip the rest of the current loop iteration [...]
Note: Note that in PHP the switch statement is considered a looping structure for the purposes of continue.

You need to use continue 2 instead:

 function filter_optionsfordash(array $data,$dash) {
    $filtered_options = array();
    $len = strlen($dash);    
    foreach ($data as $k => $value) {
      if (substr($k,0,$len) === $dash) {
        $option_name = trim(str_replace($dash . '_','',$k)); 

        switch ($option_name) {
          case 'displayColumns':
            $value = explode(',',$value);
          break;

          case 'dashletTitle':
            $option_name = 'title';
          break;

          case 'id':
          case 'module':
          case 'action':
          case 'configure':
          case 'to_pdf':
            continue 2;
          break;
        }


        $filtered_options[$option_name] = $value;         
      }
    }    

    return $filtered_options;
  }