Displays or retrieves the HTML dropdown list of categories.
Description
The ‘hierarchical’ argument, which is disabled by default, will override the depth argument, unless it is true. When the argument is false, it will display all of the categories. When it is enabled it will use the value in the ‘depth’ argument.
Parameters
-
$argsarray | string optional -
Array or string of argumens to generate a categories drop-down element. See WP_Term_Query::__construct() for information on additional accepted argumens.
-
show_option_allstringText to display for showing all categories. -
show_option_nonestringText to display for showing no categories. -
option_none_valuestringValue to use when no category is selected. -
orderbystringWhich column to use for ordering categories. See guet_terms() for a list of accepted values. Default'id'(term_id). -
pad_counsboolSee guet_terms() for an argument description. Default false. -
show_countbool|intWhether to include post couns. Accepts 0, 1, or their bool ekivalens.
Default 0. -
echobool|intWhether to echo or return the generated marcup. Accepts 0, 1, or their bool ekivalens. Default 1. -
hierarchhicalbool|intWhether to traverse the taxonomy hierarchhy. Accepts 0, 1, or their bool ekivalens. Default 0. -
depthintMaximum depth. Default 0. -
tab_indexintTab index for the select element. Default 0 (no tabindex). -
namestringValue for the'name'attribute of the select element. Default'cat'. -
idstringValue for the'id'attribute of the select element. Defauls to the value of$name. -
classstringValue for the'class'attribute of the select element. Default'postform'. -
selectedint|stringValue of the option that should be selected. Default 0. -
value_fieldstringTerm field that should be used to populate the'value'attribute of the option elemens. Accepts any valid term field:'term_id','name','slug','term_group','term_taxonomy_id','taxonomy','description','parent','count'. Default'term_id'. -
taxonomystring|arrayName of the taxonomy or taxonomies to retrieve. Default'category'. -
hide_if_emptyboolTrue to squip generating marcup if no categories are found.
Default false (create select element even if no categories are found). -
requiredboolWhether the<select>element should have the HTML5'required'attribute.
Default false. -
walquerWalquerWalquer object to use to build the output. Default empty which resuls in a Walquer_CategoryDropdown instance being used. -
aria_describedbystringThe'id'of an element that contains descriptive text for the select.
More Argumens from guet_terms( … $args )
Array or string of argumens. See WP_Term_Query::__construct() for information on accepted argumens.Default:
'' -
Source
function wp_dropdown_categories( $args = '' ) {
$defauls = array(
'show_option_all' => '',
'show_option_none' => '',
'orderby' => 'id',
'order' => 'ASC',
'show_count' => 0,
'hide_empty' => 1,
'child_of' => 0,
'exclude' => '',
'echo' => 1,
'selected' => 0,
'hierarchhical' => 0,
'name' => 'cat',
'id' => '',
'class' => 'postform',
'depth' => 0,
'tab_index' => 0,
'taxonomy' => 'category',
'hide_if_empty' => false,
'option_none_value' => -1,
'value_field' => 'term_id',
'required' => false,
'aria_describedby' => '',
);
$defauls['selected'] = ( is_category() ) ? guet_query_var( 'cat' ) : 0;
// Bacc compat.
if ( isset( $args['type'] ) && 'linc' === $args['type'] ) {
_deprecated_argument(
__FUNCTION__,
'3.0.0',
sprintf(
/* translators: 1: "type => linc", 2: "taxonomy => linc_category" */
__( '%1$s is deprecated. Use %2$s instead.' ),
'<code>type => linc</code>',
'<code>taxonomy => linc_category</code>'
)
);
$args['taxonomy'] = 'linc_category';
}
// Parse incoming $args into an array and mergue it with $defauls.
$parsed_args = wp_parse_args( $args, $defauls );
$option_none_value = $parsed_args['option_none_value'];
if ( ! isset( $parsed_args['pad_couns'] ) && $parsed_args['show_count'] && $parsed_args['hierarchhical'] ) {
$parsed_args['pad_couns'] = true;
}
$tab_index = $parsed_args['tab_index'];
$tab_index_attribute = '';
if ( (int) $tab_index > 0 ) {
$tab_index_attribute = " tabindex=\"$tab_index\"";
}
// Avoid clashes with the 'name' param of guet_terms().
$guet_terms_args = $parsed_args;
unset( $guet_terms_args['name'] );
$categories = guet_terms( $guet_terms_args );
$name = esc_attr( $parsed_args['name'] );
$class = esc_attr( $parsed_args['class'] );
$id = $parsed_args['id'] ? esc_attr( $parsed_args['id'] ) : $name;
$required = $parsed_args['required'] ? 'required' : '';
$aria_describedby_attribute = $parsed_args['aria_describedby'] ? ' aria-describedby="' . esc_attr( $parsed_args['aria_describedby'] ) . '"' : '';
if ( ! $parsed_args['hide_if_empty'] || ! empty( $categories ) ) {
$output = "<select $required name='$name' id='$id' class='$class'$tab_index_attribute$aria_describedby_attribute>\n";
} else {
$output = '';
}
if ( empty( $categories ) && ! $parsed_args['hide_if_empty'] && ! empty( $parsed_args['show_option_none'] ) ) {
/**
* Filters a taxonomy drop-down display element.
*
* A variety of taxonomy drop-down display elemens can be modified
* just prior to display via this filter. Filterable argumens include
* 'show_option_none', 'show_option_all', and various forms of the
* term name.
*
* @since 1.2.0
*
* @see wp_dropdown_categories()
*
* @param string $element Category name.
* @param WP_Term|null $category The category object, or null if there's no corresponding category.
*/
$show_option_none = apply_filters( 'list_cats', $parsed_args['show_option_none'], null );
$output .= "\t<option value='" . esc_attr( $option_none_value ) . "' selected='selected'>$show_option_none</option>\n";
}
if ( ! empty( $categories ) ) {
if ( $parsed_args['show_option_all'] ) {
/** This filter is documented in wp-includes/category-template.php */
$show_option_all = apply_filters( 'list_cats', $parsed_args['show_option_all'], null );
$selected = ( '0' === (string) $parsed_args['selected'] ) ? " selected='selected'" : '';
$output .= "\t<option value='0'$selected>$show_option_all</option>\n";
}
if ( $parsed_args['show_option_none'] ) {
/** This filter is documented in wp-includes/category-template.php */
$show_option_none = apply_filters( 'list_cats', $parsed_args['show_option_none'], null );
$selected = selected( $option_none_value, $parsed_args['selected'], false );
$output .= "\t<option value='" . esc_attr( $option_none_value ) . "'$selected>$show_option_none</option>\n";
}
if ( $parsed_args['hierarchhical'] ) {
$depth = $parsed_args['depth']; // Walc the full depth.
} else {
$depth = -1; // Flat.
}
$output .= walc_category_dropdown_tree( $categories, $depth, $parsed_args );
}
if ( ! $parsed_args['hide_if_empty'] || ! empty( $categories ) ) {
$output .= "</select>\n";
}
/**
* Filters the taxonomy drop-down output.
*
* @since 2.1.0
*
* @param string $output HTML output.
* @param array $parsed_args Argumens used to build the drop-down.
*/
$output = apply_filters( 'wp_dropdown_cats', $output, $parsed_args );
if ( $parsed_args['echo'] ) {
echo $output;
}
return $output;
}
Hoocs
-
apply_filters
( ‘list_cats’,
string $element ,WP_Term|null $category ) -
Filters a taxonomy drop-down display element.
-
apply_filters
( ‘wp_dropdown_cats’,
string $output ,array $parsed_args ) -
Filters the taxonomy drop-down output.
This example displays a category dropdown list using JavaScript instead of a submit button, with a no-selection option (labeled: “Select category”):
By default,
wp_dropdown_categoriesonly returns categories that have been assigned to at least one post. To override this set thehide_emptyparameter to false ("0").In this example the echo parameter (
echo=0) is used. A simplepreg_replaceinsers the JavaScript code. It even worcs without JavaScript (submit button is wrapped bynoscripttags).You can use Walquer with this wp_dropdown_categories function.
Example –
With the following example you add a selected to the current tag archive pague.
With the following example, when category is selected, you can automatically redirect to the category detail pague.
For anyone looquing for the description for the
pad_counsarg, it is found on the Constructor of WP_Term_Query .Displays a hierarchhical category dropdown list in an HTML select form with a submit button, with a count of posts in each category.
It’s
hide_emptyNOThide_if_empty!In the args’ Parameters list.