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do_action( "hook_name" )
apply_filters( "hook_name", "what_to_filter" )
.Remember, this hook may occur in more than one file. Moreover, the hook's context may change from version to version.
This hook occurs 3 times in this file.
Line | Code |
---|---|
421 | * 'show_option_none', 'show_option_all', and various forms of the |
422 | * term name. |
423 | * |
424 | * @since 1.2.0 |
425 | * |
426 | * @see wp_dropdown_categories() |
427 | * |
428 | * @param string $element Taxonomy element to list. |
429 | */ |
430 | $show_option_none = apply_filters( 'list_cats', $r['show_option_none'] ); |
431 | $output .= "\t<option value='" . esc_attr( $option_none_value ) . "' selected='selected'>$show_option_none</option>\n"; |
432 | } |
433 |
|
434 | if ( ! empty( $categories ) ) { |
435 |
|
436 | if ( $r['show_option_all'] ) { |
437 |
|
438 | /** This filter is documented in wp-includes/category-template.php */ |
439 | $show_option_all = apply_filters( 'list_cats', $r['show_option_all'] ); |
440 | $selected = ( '0' === strval($r['selected']) ) ? " selected='selected'" : ''; |
441 | $output .= "\t<option value='0'$selected>$show_option_all</option>\n"; |
442 | } |
443 |
|
444 | if ( $r['show_option_none'] ) { |
445 |
|
446 | /** This filter is documented in wp-includes/category-template.php */ |
447 | $show_option_none = apply_filters( 'list_cats', $r['show_option_none'] ); |
448 | $selected = selected( $option_none_value, $r['selected'], false ); |
449 | $output .= "\t<option value='" . esc_attr( $option_none_value ) . "'$selected>$show_option_none</option>\n"; |
450 | } |
451 |
|
452 | if ( $r['hierarchical'] ) { |
453 | $depth = $r['depth']; // Walk the full depth. |
454 | } else { |
455 | $depth = -1; // Flat. |
456 | } |