循环内的函数

Question

function mm_posts() {
  $result = '';      

  if ( have_posts() ) :
    query_posts('cat=5&posts_per_page=4');
    while ( have_posts() ) : the_post();

    $post_thumbnail_id = get_post_thumbnail_id();
    $post_thumbnail_url = wp_get_attachment_image_src( $post_thumbnail_id, array(300, 200) );

    function mega_thmb() {
      if ( has_post_thumbnail() ) : 
        $img = '<img src="' .  $post_thumbnail_url[0] . '" alt="" class="img-responsive">';
      else :
        $img = '<img src="' .  get_template_directory_uri() . '/img/no-image.gif" alt="" class="img-responsive">';
      endif;

      return $img;
    }

      $result .= '
        <div class="col-md-3">' .
          mega_thmb() .
          '<div>Sport</div>
          <div>Lorem ipsum dolor sit amet</div>
        </div>';
    endwhile;
    wp_reset_query();
  endif;
  return $result;
}

Php displays error : Fatal error: Cannot redeclare mega_thmb() (previously declared in ...

What should I do? How write function inside the loop?

Answer 1

. Structure your code as follows. Additionally, each time the loop is run you're declaring the function again, even though it's already in memory. It needs to be outside the loop. Best practice would be to not embed the function at all

function mega_thmb() {
      if ( has_post_thumbnail() ) : 
        $img = '<img src="' .  $post_thumbnail_url[0] . '" alt="" class="img-responsive">';
      else :
        $img = '<img src="' .  get_template_directory_uri() . '/img/no-image.gif" alt="" class="img-responsive">';
      endif;

      return $img;
    }   

function mm_posts() {
  $result = '';      

  if ( have_posts() ) :
    query_posts('cat=5&posts_per_page=4');
    while ( have_posts() ) : the_post();

    $post_thumbnail_id = get_post_thumbnail_id();
    $post_thumbnail_url = wp_get_attachment_image_src( $post_thumbnail_id, array(300, 200) );



      $result .= '
        <div class="col-md-3">' .
          mega_thmb() .
          '<div>Sport</div>
          <div>Lorem ipsum dolor sit amet</div>
        </div>';
    endwhile;
    wp_reset_query();
  endif;
  return $result;
}

I suggest reading the PHP documents, and consulting a few tutorials before moving any further. There are probably some other changes that need to be made to your code to make it completely correct, but please don't define functions inside of other functions, especially inside loops. Read the manual.