Wordpress下拉类别导航

Question

我在菜单中创建了一个带有下拉列表的目录网站，允许用户在整个类别和子类别中导航。我使用wp_dropdown_categories（）来显示菜单。此处共享的javascript http://codex.wordpress.org/Function_Reference/wp_dropdown_categories允许用户选择类别并导航到该页面。当＆＃39;所有类别＆＃39;被选中，没有任何反应。如何添加该功能？

        $category = get_category( get_query_var( 'cat' ) );
        $cat_id = $category->cat_ID; 
        $cat_name = $category->name;

        $cat_id2 = get_category_by_slug($cats[2]);

            $args = array(
            'show_option_all'    => 'All Categories',
            'show_option_none'   => 'BROWSE',
            'orderby'            => 'NAME', 
            'order'              => 'ASC',
            'show_count'         => 0,
            'hide_empty'         => 1, 
            'child_of'           => 0,
            'exclude'            => 1,
            'echo'               => 1,
            'selected'           => $cat_id2->term_id,
            'hierarchical'       => 1, 
            'name'               => 'cat',
            'id'                 => '',
            'class'              => 'postform',
            'depth'              => 1,
            'tab_index'          => 0,
            'taxonomy'           => 'category',
            'hide_if_empty'      => false,
        );

        wp_dropdown_categories( $args );

                $cat_id3 = get_category_by_slug($cats[3]);

            $args2 = array(
                'show_option_all'    => 'All ' . $cat_id2->name,
                'show_option_none'   => '',
                'orderby'            => 'NAME', 
                'order'              => 'ASC',
                'show_count'         => 0,
                'hide_empty'         => 1, 
                'child_of'           => $cat_id2->term_id,
                'exclude'            => 1,
                'echo'               => 1,
                'selected'           => $cat_id3->term_id,
                'hierarchical'       => 1, 
                'name'               => 'cat2',
                'id'                 => '',
                'class'              => 'postform',
                'depth'              => 1,
                'tab_index'          => 0,
                'taxonomy'           => 'category',
                'hide_if_empty'      => false,
            );

            //print $cats[2];

            if(($cats[1] == "category") AND ($cats[2] != '')) { wp_dropdown_categories( $args2 ); }

            $cat_id4 = get_category_by_slug($cats[4]);

            $args3 = array(
                'show_option_all'    => '',
                'show_option_none'   => 'All ' . $cat_id3->name,
                'orderby'            => 'NAME', 
                'order'              => 'ASC',
                'show_count'         => 0,
                'hide_empty'         => 1, 
                'child_of'           => $cat_id3->term_id,
                'exclude'            => 1,
                'echo'               => 1,
                'selected'           => $cat_id4->term_id,
                'hierarchical'       => 1, 
                'name'               => 'cat3',
                'id'                 => '',
                'class'              => 'postform',
                'depth'              => 1,
                'tab_index'          => 0,
                'taxonomy'           => 'category',
                'hide_if_empty'      => false,
            );

            if($cats[3] != '') { wp_dropdown_categories( $args3 ); }

Javascript

<script type="text/javascript"><!--
var dropdown = document.getElementById("cat");
function onCatChange() {
    if ( dropdown.options[dropdown.selectedIndex].value > 0 ) {
        location.href = "<?php echo get_option('home');
?>/?cat="+dropdown.options[dropdown.selectedIndex].value;
    }
}
dropdown.onchange = onCatChange;

 --></script>

<script type="text/javascript"><!--
var dropdown2 = document.getElementById("cat2");
function onCatChange2() {
    if ( dropdown2.options[dropdown2.selectedIndex].value > 0 ) {
        location.href = "<?php echo get_option('home');
?>/?cat="+dropdown2.options[dropdown2.selectedIndex].value;
    }
}
dropdown2.onchange = onCatChange2;

--></script>

<script type="text/javascript"><!--
var dropdown3 = document.getElementById("cat3");
function onCatChange3() {
    if ( dropdown3.options[dropdown3.selectedIndex].value > 0 ) {
        location.href = "<?php echo get_option('home');
?>/?cat="+dropdown3.options[dropdown3.selectedIndex].value;
    }
}
dropdown3.onchange = onCatChange3;

--></script>