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画像ファイルの情報を取得する

2009年　5月 29日 admin

画像idからURIを取得

アップロード画像の各サイズ (thumbnail, medium, large, full) の URL は、アタッチメントの ID が分かれば wp_get_attachment_image_src(　$id, $size ) で取得出来ます。
この関数は画像の URL と　width, height を配列にして返します。

 516  /**
 517   * Retrieve img HTML content for an image to represent an attachment.
 518   *
 519   * @see wp_get_attachment_image_src() Returns img HTML element based on array.
 520   * @since 2.5.0
 521   *
 522   * @param int $attachment_id Image attachment ID.
 523   * @param string $size Optional, default is 'thumbnail'.
 524   * @param bool $icon Optional, default is false. Whether it is an icon.
 525   * @return string HTML img element or empty string on failure.
 526   */
 527  function wp_get_attachment_image($attachment_id, $size = 'thumbnail', $icon = false) {
 528  
 529      $html = '';
 530      $image = wp_get_attachment_image_src($attachment_id, $size, $icon);
 531      if ( $image ) {
 532          list($src, $width, $height) = $image;
 533          $hwstring = image_hwstring($width, $height);
 534          if ( is_array($size) )
 535              $size = join('x', $size);
 536          $html = '<img src="'.attribute_escape($src).'" '.$hwstring.'class="attachment-'.attribute_escape($size).'" alt="" />';
 537      }
 538  
 539      return $html;
 540  }

 
 488  /**
 489   * Retrieve an image to represent an attachment.
 490   *
 491   * A mime icon for files, thumbnail or intermediate size for images.
 492   *
 493   * @since 2.5.0
 494   *
 495   * @param int $attachment_id Image attachment ID.
 496   * @param string $size Optional, default is 'thumbnail'.
 497   * @param bool $icon Optional, default is false. Whether it is an icon.
 498   * @return bool|array Returns an array (url, width, height), or false, if no image is available.
 499   */
 500  function wp_get_attachment_image_src($attachment_id, $size='thumbnail', $icon = false) {
 501  
 502      // get a thumbnail or intermediate image if there is one
 503      if ( $image = image_downsize($attachment_id, $size) )
 504          return $image;
 505  
 506      if ( $icon && $src = wp_mime_type_icon($attachment_id) ) {
 507          $icon_dir = apply_filters( 'icon_dir', ABSPATH . WPINC . '/images/crystal' );
 508          $src_file = $icon_dir . '/' . basename($src);
 509          @list($width, $height) = getimagesize($src_file);
 510      }
 511      if ( $src && $width && $height )
 512          return array( $src, $width, $height );
 513      return false;
 514  }

Well, I’m not sure if there’s a better way, but this worked

$image=wp_get_attachment_image($num, 'large', false);
$imagepieces = explode(" ", $image);
$imagepath = substr($imagepieces[1],4);

In fact this is even cleaner, thanks to my buddies on Yay:

$image=wp_get_attachment_image($num, 'large', false);
$imagepieces = explode('"', $image);
$imagepath = $imagepieces[1];

Get ‘large’ image attachments inside loop?

エントリのidからその投稿に利用されている画像を探す。

/**
2487   * Retrieve attachment meta field for attachment ID.
2488   *
2489   * @since 2.1.0
2490   *
2491   * @param int $post_id Attachment ID
2492   * @param bool $unfiltered Optional, default is false. If true, filters are not run.
2493   * @return string|bool Attachment meta field. False on failure.
2494   */
2495  function wp_get_attachment_metadata( $post_id, $unfiltered = false ) {
2496      $post_id = (int) $post_id;
2497      if ( !$post =& get_post( $post_id ) )
2498          return false;
2499  
2500      $data = get_post_meta( $post->ID, '_wp_attachment_metadata', true );
2501      if ( $unfiltered )
2502          return $data;
2503      return apply_filters( 'wp_get_attachment_metadata', $data, $post->ID );
2504  }
2505