Wrap a post image with a div if it doesn't have a caption

Question

I've tried the below code to wrap a post image with a div and it works. The problem I'm having is if the image has a caption. It screws up the the code that is generated when a caption is set for the image.

How can I modify this code to only be applied for an image with no caption?

if(is_admin()){

  add_filter('image_send_to_editor', 'wrap_my_div', 10, 8);

  function wrap_my_div($html, $id, $caption, $title, $align, $url, $size, $alt){
    return '<div class="mydiv-'.$size.'" id="mydiv-'.$id.'">'.$html.'</div>';
  }
}

Answer 1

You could try with

if(is_admin()){

  add_filter('image_send_to_editor', 'wrap_my_div', 10, 8);

  function wrap_my_div($html, $id, $caption, $title, $align, $url, $size, $alt) {
     if( isset($caption) && $caption )
       return $html;
     else
       return '<div class="mydiv" id="mydiv-'.$id.'">'.$html.'</div>';
  }
}