在循环中显示不同的数组元素

I have an array of objects:

Array
(
    [0] => stdClass Object
        (
            [id] => 24
            [ban_id] => 163
            [ban_url] => http://www.website.com/wp-content/uploads/2014/04/72890.jpg
        )

    [1] => stdClass Object
        (
            [id] => 25
            [ban_id] => 162
            [ban_url] => http://www.website.com/wp-content/uploads/2014/04/46860.jpg
        )

    [2] => stdClass Object
        (
            [id] => 26
            [ban_id] => 169
            [ban_url] => http://www.website.com/wp-content/uploads/2014/04/46871.jpg
        )

)

I also have a Wordpress loop:

$count = 0;
while ( have_posts() ) : the_post();
   $count++;
   $show_ad = $count%3 == 0;
   if ( $show_ad ):
      echo '<img src="..." alt="" />';
   endif;
endwhile;

I would like to display one (or even more, depends on the user's choice) of the images if $show_ad is equal to true (every 3 posts in this case).

For example, 1 different image every 3 posts :

[Wordpress POST 1]
[Wordpress POST 2]
[Wordpress POST 3]
   [Image 0]
[Wordpress POST 1]
[Wordpress POST 2]
[Wordpress POST 3]
   [Image 1]
[Wordpress POST 1]
[Wordpress POST 2]
[Wordpress POST 3]
   [Image 2]
[Wordpress POST 1]
[Wordpress POST 2]
[Wordpress POST 3]
   [Image 0]
...

Or another example, 2 different images every 3 posts :

[Wordpress POST 1]
[Wordpress POST 2]
[Wordpress POST 3]
   [Image 0]
   [Image 1]
[Wordpress POST 1]
[Wordpress POST 2]
[Wordpress POST 3]
   [Image 2]
   [Image 0]
[Wordpress POST 1]
[Wordpress POST 2]
[Wordpress POST 3]
   [Image 1]
   [Image 2]
[Wordpress POST 1]
[Wordpress POST 2]
[Wordpress POST 3]
   [Image 0]
   [Image 1]
...

Any help will be greatly appreciated.

After reviewing your response, i believe the best way to answer your question is to create an incremental variable as well for your banner ads.

Review the following changes to your while loop.

$count = 0;
$banner_count = 0;
while ( have_posts() ) : the_post();
   $count++;
   $show_ad = $count%3 == 0;
   if ( $show_ad ):
      //I dont know the name of the banner object so i gave it $banner_object
      $banner_url = $banner_object[$banner_count]->ban_url;
      echo '<img src="' .$banner_url .'" alt="" />';

      //Increment Banner
      $banner_count++;

   endif;

Hope that helps! Let me know if your looking for something else. If you only have a certain amount banners, then you may want to reset banner_count when it reaches the end of your banners object. See code below

$count = 0;
$banner_count = 0;
while ( have_posts() ) : the_post();
   $count++;
   $show_ad = $count%3 == 0;
   if ( $show_ad ):

      $banner_url = $banner_object[$banner_count]->ban_url;
      echo '<img src="' .$banner_url .'" alt="" />';

      //Increment Banner
      $banner_count++;

      //If reached the end of the banner count
      if($banner_count > count($banner_object)) { $banner_count = 0; }

   endif;