$_FILES 在 update_post_meta WordPress 中返回空

Question

我尝试在保存后使用 $_FILES 访问我的自定义字段文件（图像）值，但它 返回一个空字符串，我尝试使用 $_POST 但它仅返回我想要获取文件名 + mime 类型的文件名 我尝试使用 $FILES[input_name][type] 它也返回一个空值。我尝试了很多解决方案但没有成功

//theme shop menu
class BakentakeShopMenu{
    function __construct(){
        //register shop menu custom post type
        add_action( 'init', array($this,'create_menuitem_cpt'), 1, );
        //register custom fields for shop menu post type
        add_action("add_meta_boxes",[$this,'shop_items_custom_fields'],2);
        
        add_action('save_post',[$this,'save_shop_items_fields']);
        add_action("rest_api_init",[$this,"add_menu_data_to_rest"]);
    }

    // add menu items to the rest api 
    function add_menu_data_to_rest(){
        // register_rest_route("wp/v2","menu_data",[
        //  "methods" => "GET",
        //  "callback" => [$this,"set_menu_data_to_rest_config"]
        // ]);
        register_rest_field("menuitem","menuData",array(
            "get_callback" => [$this,'register_menu_item_data_rest_field'],
            'update_callback' => null,
            'schema' => null,
            )
        );
    }

    function register_menu_item_data_rest_field($post){
        $itemName = get_post_meta($post['id'],'item_name_value',true);
        $itemDescription = get_post_meta($post['id'],'item_description_value',true);
        $itemPrice = get_post_meta($post['id'],'item_price_value',true);
        $itemDiscountPrice = get_post_meta($post['id'],'item_discount_value',true);
        $itemImage = get_post_meta($post['id'],'item_image_value',true);

        return [$itemName,$itemDescription,$itemPrice,$itemDiscountPrice,$itemImage];
    }

// Register Custom Post Type Menu Item
function create_menuitem_cpt() {
    $labels = array(
        'name' => _x( 'Menu Items', 'Post Type General Name', 'textdomain' ),
        'singular_name' => _x( 'Menu Item', 'Post Type Singular Name', 'textdomain' ),
        'menu_name' => _x( 'Menu Items', 'Admin Menu text', 'textdomain' ),
        'name_admin_bar' => _x( 'Menu Item', 'Add New on Toolbar', 'textdomain' ),
        'archives' => __( 'Menu Item Archives', 'textdomain' ),
        'attributes' => __( 'Menu Item Attributes', 'textdomain' ),
        'parent_item_colon' => __( 'Parent Menu Item:', 'textdomain' ),
        'all_items' => __( 'All Menu Items', 'textdomain' ),
        'add_new_item' => __( 'Add New Menu Item', 'textdomain' ),
        'add_new' => __( 'Add New', 'textdomain' ),
        'new_item' => __( 'New Menu Item', 'textdomain' ),
        'edit_item' => __( 'Edit Menu Item', 'textdomain' ),
        'update_item' => __( 'Update Menu Item', 'textdomain' ),
        'view_item' => __( 'View Menu Item', 'textdomain' ),
        'view_items' => __( 'View Menu Items', 'textdomain' ),
        'search_items' => __( 'Search Menu Item', 'textdomain' ),
        'not_found' => __( 'Not found', 'textdomain' ),
        'not_found_in_trash' => __( 'Not found in Trash', 'textdomain' ),
        'featured_image' => __( 'Featured Image', 'textdomain' ),
        'set_featured_image' => __( 'Set featured image', 'textdomain' ),
        'remove_featured_image' => __( 'Remove featured image', 'textdomain' ),
        'use_featured_image' => __( 'Use as featured image', 'textdomain' ),
        'insert_into_item' => __( 'Insert into Menu Item', 'textdomain' ),
        'uploaded_to_this_item' => __( 'Uploaded to this Menu Item', 'textdomain' ),
        'items_list' => __( 'Menu Items list', 'textdomain' ),
        'items_list_navigation' => __( 'Menu Items list navigation', 'textdomain' ),
        'filter_items_list' => __( 'Filter Menu Items list', 'textdomain' ),
    );
    $args = array(
        'label' => __( 'Menu Item', 'textdomain' ),
        'description' => __( '', 'textdomain' ),
        'labels' => $labels,
        'menu_icon' => 'dashicons-cart',
        'supports' => array('thumbnail', 'trackbacks', 'page-attributes', 'post-formats', 'custom-fields'),
        'taxonomies' => array(),
        'public' => true,
        'show_ui' => true,
        'show_in_menu' => true,
        'menu_position' => 5,
        'show_in_admin_bar' => true,
        'show_in_nav_menus' => true,
        'can_export' => true,
        'has_archive' => true,
        'hierarchical' => false,
        'exclude_from_search' => false,
        'show_in_rest' => true,
        'publicly_queryable' => true,
        'capability_type' => 'post',
    );
    register_post_type( 'menuitem', $args );
}

    //add custom field settings
    function shop_items_custom_fields(){
        add_meta_box(
            'shop_item',
            'shop items',
            array($this,'shop_items_config'),
            'menuitem',
            'normal',
            'low',
            ''

        );
    }
    // save custom field values 
    function save_shop_items_fields($post_id ){
        //item name
            update_post_meta(
                $post_id ,
                "item_name_value",
                $_POST['item_name']
            );
        //item description
            update_post_meta(
                $post_id ,
                "item_description_value",
                $_POST['item_description']
            );
        //item price
            update_post_meta(
                $post_id ,
                "item_price_value",
                $_POST['item_price']
            );
        //discount price
            update_post_meta(
                $post_id ,
                "item_discount_value",
                $_POST['item_price']
            );
        //Image
            update_post_meta(
                $post_id ,
                "item_image_value",
                $_FILES['item_image']
            );          
    }   
    //custom fields config
    function shop_items_config($post){
        $itemName = get_post_meta($post->ID,'item_name_value',true);
        $itemDescription = get_post_meta($post->ID,'item_description_value',true);
        $itemPrice = get_post_meta($post->ID,'item_price_value',true);
        $itemDiscountPrice = get_post_meta($post->ID,'item_discount_value',true);
        $itemImage = get_post_meta($post->ID,'item_image_value',true);

        //upload images
        $wordpress_upload_dir = wp_upload_dir();
        $file_path = $wordpress_upload_dir['path'] . '/' . $itemImage;
        $file = "https://upload.wikimedia.org/wikipedia/commons/thumb/b/b6/Image_created_with_a_mobile_phone.png/1200px-Image_created_with_a_mobile_phone.png";
        ?>
        <form action = "" method="POST" enctype="multipart/form-data">
            <h1><?php print_r($itemImage) ?></h1>
            <div class="shop-items-form">
                <div class="shop-items-form-field">
                    <label for="item-name">Item Name</label>
                    <input type="text" name="item_name" value="<?php echo $itemName ?>"/>
                </div>
                <div class="shop-items-form-field">
                    <label for="item-description">Item Description</label>
                    <textarea name="item_description"><?php echo $itemDescription ?></textarea>
                </div>
                <div class="shop-items-form-field__wraper">
                    <div class="shop-items-form-field">
                        <label for="itemPrice">Item Price</label>
                        <input type="number" name="item_price" value="<?php echo $itemPrice ?>"/>
                    </div>
                    <div class="shop-items-form-field">
                        <label for="discount-price">Discount Price</label>
                        <input type="number" name="discount_price" value="<?php echo $itemDiscountPrice ?>"/>
                    </div>
                </div>
                <div class="shop-items-form-field">
                    <label for="discount-price">Add Item Image</label>
                    <input type="file" name="item_image" accept="image/png,image/jpeg" value=<?php $itemImage ?>/>
                </div>
            </div>
        </form>
        <?php
    }
};

new BakentakeShopMenu;

Answer 1

尽管您的表单允许文件上传，但它包含在默认的 Wordpress Post 表单中，因此您必须让 Wordpress 知道该表单可能包含文件。默认情况下，此选项在所有帖子表单（帖子、页面、自定义帖子类型等）中处于禁用状态。

<?php
// Add this hook on your init file
    add_action('post_edit_form_tag','update_edit_form'));
// Create the function that allows file uploads on post forms
    function update_edit_form(){
      echo 'enctype="multipart/form-data"';
    }
?>