attachment_fields_to_edit │ filter-hook │ WP 2.5.0

Allows you to add a custom field to an image (the field's HTML on the attachment editing screen).

This hook only adds a meta-field; it does not save its data. Use the attachment_fields_to_save hook to save it.

Usage

add_filter( 'attachment_fields_to_edit', 'wp_kama_attachment_fields_to_edit_filter', 10, 2 );

/**
 * Function for `attachment_fields_to_edit` filter-hook.
 * 
 * @param array   $form_fields An array of attachment form fields.
 * @param WP_Post $post        The WP_Post attachment object.
 *
 * @return array
 */
function wp_kama_attachment_fields_to_edit_filter( $form_fields, $post ){

	// filter...
	return $form_fields;
}

$form_fields(array)

The attachment form field data.

$post(WP_Post)

The attachment post object.

Examples

#1 Add a meta-field for an image

// Add a meta-field for the image
add_filter( 'attachment_fields_to_edit', 'pon_attachment_fields_to_edit', null, 2 );
function pon_attachment_fields_to_edit( $form_fields, $post ){

	$form_fields['carousel_price'] = array(
		'label' => 'Price (if needed)',
		'input' => '',
		'value' => get_post_meta( $post->ID, 'carousel_price', true )
	);

	return $form_fields;
}

// Save the meta-field data
add_filter("attachment_fields_to_save", "pon_attachment_fields_to_save", null, 2);
function pon_attachment_fields_to_save($post, $attachment) {
	if( isset($attachment['carousel_price']) ){
		update_post_meta( $post['ID'], 'carousel_price', $attachment['carousel_price'] );
	}
	else
		delete_post_meta( $post['ID'], 'carousel_price' );

	return $post;
}

The result: