Question

我是WordPress插件开发的新手。我有以下插件的表单方法代码。当我输入title字段中的任何内容并保存时，它会给出警告：extract（）期望参数1为数组，在/ Applications / XAMPP / xamppfiles / htdocs / NGO / wp-content / plugins / messagner <中给出null / em>

public function form($instance) { extract($instance); print_r($instance); ?> <p> <label for="<?php echo $this->get_field_id('title');?> ">Title</label> <input class="widefat" id = "<?php echo $this->get_field_id('title');?>" name = "<?php echo $this->get_field_name('title');?>" value = "<?php if(isset($title)) echo esc_attr($title); ?>" /> </p> <p> <label for="<?php echo $this->get_field_id('description'); ?>"></label> <textarea class = "widefat" rows = 10 id = "<?php echo $this->get_field_id('description');?>" name = "<?php echo $this->get_field_name('description'); ?>" value = "<?php if(isset($description)) echo esc_attr($description); ?>" > </textarea> </p> <?php }?>

我不知道我在哪里犯了一些愚蠢的错误请帮忙。谢谢。

Answer 1

看了这个代码然后跟着，在这种情况下，$ instance返回为null。它应该得到数组。

 <?php
    /**
     * Example Widget Class
     */
    class example_widget extends WP_Widget {


        /** constructor -- name this the same as the class above */
        function example_widget() {
            parent::WP_Widget(false, $name = 'Example Text Widget');    
        }

        /** @see WP_Widget::widget -- do not rename this */
        function widget($args, $instance) { 
            extract( $args );
            $title      = apply_filters('widget_title', $instance['title']);
            $message    = $instance['message'];
            ?>
                  <?php echo $before_widget; ?>
                      <?php if ( $title )
                            echo $before_title . $title . $after_title; ?>
                                <ul>
                                    <li><?php echo $message; ?></li>
                                </ul>
                  <?php echo $after_widget; ?>
            <?php
        }

        /** @see WP_Widget::update -- do not rename this */
        function update($new_instance, $old_instance) {     
            $instance = $old_instance;
            $instance['title'] = strip_tags($new_instance['title']);
            $instance['message'] = strip_tags($new_instance['message']);
            return $instance;
        }

        /** @see WP_Widget::form -- do not rename this */
        function form($instance) {  

            $title      = esc_attr($instance['title']);
            $message    = esc_attr($instance['message']);
            ?>
             <p>
              <label for="<?php echo $this->get_field_id('title'); ?>"><?php _e('Title:'); ?></label> 
              <input class="widefat" id="<?php echo $this->get_field_id('title'); ?>" name="<?php echo $this->get_field_name('title'); ?>" type="text" value="<?php echo $title; ?>" />
            </p>
            <p>
              <label for="<?php echo $this->get_field_id('message'); ?>"><?php _e('Simple Message'); ?></label> 
              <input class="widefat" id="<?php echo $this->get_field_id('message'); ?>" name="<?php echo $this->get_field_name('message'); ?>" type="text" value="<?php echo $message; ?>" />
            </p>
            <?php 
        }


    } // end class example_widget
    add_action('widgets_init', create_function('', 'return register_widget("example_widget");'));
    ?>

WordPress插件开发时出错，PHP提取功能

1 个答案: