下面由WordPress教程欄目給大家介紹怎么為WordPress小工具添加CSS類選項，希望對需要的朋友有所幫助！

WordPress 小工具可以重復使用，相同的小工具樣式也是相同的，如果想自定義某個前臺添加的小工具樣式，與其它不同，可以通過查看原代碼，找到它的id，比如搜索小工具會看到類似的：

<section id="search-2" class="widget widget_search">

其中search-2就是這個小工具的ID，可以用#search-2定義樣式，不過這個后綴的編號并不是固定的，下次添加可能會變，需要再次編輯之前的樣式，有些麻煩。

可以通過下面的代碼，給現有的小工具統一增加CSS類選項，將代碼添加到當前主題函數模板functions.php中即可，效果如圖：

代碼一　

只加一個CSS類選項

function zm_widget_form_extend( $instance, $widget ) {   if ( !isset($instance['classes']) ) $instance['classes'] = null; $row = "<p>n"; $row .= "t<label for='widget-{$widget->id_base}-{$widget->number}-classes'>CSS類</label>n"; $row .= "t<input type='text' name='widget-{$widget->id_base}[{$widget->number}][classes]' id='widget-{$widget->id_base}-{$widget->number}-classes' class='widefat' value='{$instance['classes']}'/>n"; $row .= "</p>n"; echo $row; return $instance; } add_filter('widget_form_callback', 'zm_widget_form_extend', 10, 2);   function zm_widget_update( $instance, $new_instance ) { $instance['classes'] = $new_instance['classes']; return $instance; } add_filter( 'widget_update_callback', 'zm_widget_update', 10, 2 );   function zm_dynamic_sidebar_params( $params ) { global $wp_registered_widgets; $widget_id    = $params[0]['widget_id']; $widget_obj    = $wp_registered_widgets[$widget_id]; $widget_opt    = get_option($widget_obj['callback'][0]->option_name); $widget_num    = $widget_obj['params'][0]['number'];   if ( isset($widget_opt[$widget_num]['classes']) && !empty($widget_opt[$widget_num]['classes']) ) $params[0]['before_widget'] = preg_replace( '/class="/', "class="{$widget_opt[$widget_num]['classes']} ", $params[0]['before_widget'], 1 ); return $params; } add_filter( 'dynamic_sidebar_params', 'zm_dynamic_sidebar_params' );

代碼二　

添加ID及CSS類下拉選項

function zm_widget_form_extend( $instance, $widget ) { if ( !isset( $instance['classes'] ) ) $instance['classes'] = null;   if ( !isset( $instance['custom_id'] ) ) $instance['custom_id'] = null;   $class_prefix = 'widget-';  $myclass = array( 'default'  => '默認', 'blue'     => '藍色', 'yellow'   => '黃色', 'black'    => '黑色', );   $row = "<p>n"; $row .= "t<label for='widget-{$widget->id_base}-{$widget->number}-custom_id'>添加ID</label>n"; $row .= "t<input type='text' name='widget-{$widget->id_base}[{$widget->number}][custom_id]' id='widget-{$widget->id_base}-{$widget->number}-custom_id' class='widefat' value='{$instance['custom_id']}' />n"; $row .= "t<label for='widget-{$widget->id_base}-{$widget->number}-classes'>CSS類</label>n"; $row .= "t<select name='widget-{$widget->id_base}[{$widget->number}][classes]' id='widget-{$widget->id_base}-{$widget->number}-classes' class='widefat'>"; foreach( $myclass as $key => $class ) { $selected = null; if( $class_prefix.$key == $instance['classes'] ) $selected = 'selected = "selected"'; $row .= "t<option value='$class_prefix$key' $selected>$class</value>n"; } $row .= "</select>n"; echo $row; return $instance; } add_filter('widget_form_callback', 'zm_widget_form_extend', 10, 2);   function zm_widget_update( $instance, $new_instance ) { $instance['classes'] = $new_instance['classes']; $instance['custom_id'] = $new_instance['custom_id']; return $instance; } add_filter( 'widget_update_callback', 'zm_widget_update', 10, 2 );   function zm_dynamic_sidebar_params( $params ) { global $wp_registered_widgets; $widget_id  = $params[0]['widget_id']; $widget_obj = $wp_registered_widgets[$widget_id]; $widget_opt = get_option($widget_obj['callback'][0]->option_name); $widget_num = $widget_obj['params'][0]['number'];   if ( isset( $widget_opt[$widget_num]['classes'] ) && !empty( $widget_opt[$widget_num]['classes'] ) ) $params[0]['before_widget'] = preg_replace( '/class="/', "class="{$widget_opt[$widget_num]['classes']} ", $params[0]['before_widget'], 1 ); if ( isset($widget_opt[$widget_num]['custom_id']) && !empty($widget_opt[$widget_num]['custom_id']) ) $params[0]['before_widget'] = preg_replace( '/id=".*?"/', "id="{$widget_opt[$widget_num]['custom_id']}"", $params[0]['before_widget'], 1 ); return $params; } add_filter( 'dynamic_sidebar_params', 'zm_dynamic_sidebar_params' );

代碼中預設了CSS類名稱，可能使用更方便些。

缺點：添加的選項位置在其它小工具選項的上面，需要改進一下。