下午好

遵循此页面成功地将Metabox字段添加到我的管理页面，现在我正在尝试使其对我有用：https://paulund.co.uk/create-custom-meta-boxes

我正在尝试为我的页面制作一个简单的食谱帖子，我希望能够在一个字段中输入多个成分。。。理想情况下，每行一个。然后将该元数据输出为数组，用于/每次处理，以便在我的页面上创建列表。

我在函数中添加了以下内容。php：

// Lets get meta
    function add_embed_recipe_meta_box() {
        add_meta_box(
            \'embed_recipe_meta_box\',           // $id
            \'Recipe Post meta box\',            // $title
            \'show_embed_recipe_meta_box\',      // $callback
            \'post\',                            // $page
            \'normal\',                          // $context
            \'high\');                           // $priority
    }
    add_action(\'add_meta_boxes\', \'add_embed_recipe_meta_box\');

// Show the meta box in admin
    function show_embed_recipe_meta_box() {
        global $post;  
               $meta = get_post_meta($post->ID, \'recipe_embed\', true);  

       // use nonce for verification  
        echo \'<input type="hidden" name="custom_meta_box_nonce" value="\'.wp_create_nonce(basename(__FILE__)).\'" />\';  

       echo \'<table class="form-table">\';   

            echo \'<tr>
                <th><label for="recipe_embed">Ingredients</label></th>
                <td><textarea name="recipe_embed" id="recipe_embed" cols="60" rows="1">\'.$meta.\'</textarea></td>
                </tr>\';

        echo \'</table>\';
    }

// Save the meta data
    function save_recipe_embed($post_id) {   
        // verify nonce
        if (!wp_verify_nonce($_POST[\'custom_meta_box_nonce\'], basename(__FILE__)))
            return $post_id;

        // check autosave
        if (defined(\'DOING_AUTOSAVE\') && DOING_AUTOSAVE)
            return $post_id;

        // check permissions
        if (\'page\' == $_POST[\'post_type\']) {
            if (!current_user_can(\'edit_page\', $post_id))
                return $post_id;
            } elseif (!current_user_can(\'edit_post\', $post_id)) {
                return $post_id;
        }  

        $old = get_post_meta($post_id, "recipe_embed", true);

        $new = $_POST["recipe_embed"];

        if ($new && $new != $old) {
            update_post_meta($post_id, "recipe_embed", $new);
        } elseif (\'\' == $new && $old) {
            delete_post_meta($post_id, "recipe_embed", $old);
        }
    }
    add_action(\'save_post\', \'save_recipe_embed\');

并使用以下代码调用元数据：

<?php $recipe_embed = get_post_meta($post->ID, "recipe_embed", true);
   if($recipe_embed != ""){ //content for true if statement below ?>

   <div style ="background: green;">     
   <?php echo $recipe_embed; //this is the content of the value ?>
    </div> 

<?php }   //close the if statement ?>   

在我的Metabox中添加一个字段并稍后显示该数据效果很好，但我在尝试向输入中添加数组时迷失了方向。非常感谢您的建议。或者其他更好的方法来完成相同的任务：）

谢谢

$recipe_embed = get_post_meta( $post->ID, "recipe_embed", true );

if ( ! empty( $recipe_embed ) ): ?>

    <div style="background: green;">
        <?php

        // normalize returns
        $recipe_embed = str_replace( "\\n", "\\r", $recipe_embed );

        // convert to array and remove empty items
        $ingredients  = array_filter( explode( "\\r", $recipe_embed ) );

        // list items
        echo "<ul class=\'ingredients\'>";
        foreach ( $ingredients as $ingredient ) {
            echo "<li class=\'ingredient\' >$ingredient</li>";
        }
        echo "</ul>";

        ?>
    </div>

<?php endif; // $recipe_embed

<?php

function add_embed_recipe_meta_box() {
    add_meta_box( \'embed_recipe_meta_box\',     // $id
            \'Recipe Post meta box\',            // $title
            \'show_embed_recipe_meta_box\',      // $callback
            \'post\',                            // $page
            \'normal\',                          // $context
            \'high\' );
}

add_action( "add_meta_boxes", "add_embed_recipe_meta_box" );

function show_embed_recipe_meta_box( $post ) {
    $meta = get_post_meta( $post->ID, \'recipe_embed\', true );

    wp_nonce_field( basename( __FILE__ ), "recipe-meta-box-nonce" );

    ?>
    <table class="form-table">
        <tr>
            <th><label for="recipe_embed">Ingredients</label></th>
            <td><textarea name="recipe_embed" id="recipe_embed" cols="60" rows="10"><?php echo $meta; ?></textarea></td>
        </tr>
    </table>
    <?php
}

function save_recipe_embed( $post_id, $post, $update ) {
    if ( ! isset( $_POST[ "recipe-meta-box-nonce" ] ) || ! wp_verify_nonce( $_POST[ "recipe-meta-box-nonce" ], basename( __FILE__ ) ) ) {
        return $post_id;
    }

    if ( ! current_user_can( "edit_post", $post_id ) ) {
        return $post_id;
    }

    if ( defined( "DOING_AUTOSAVE" ) && DOING_AUTOSAVE ) {
        return $post_id;
    }

    $slug = "post";
    if ( $slug != $post->post_type ) {
        return $post_id;
    }

    $recipe_embed = \'\';
    if ( isset( $_POST[ "recipe_embed" ] ) ) {
        $recipe_embed = $_POST[ "recipe_embed" ];
    }
    update_post_meta( $post_id, "recipe_embed", $recipe_embed );
}

add_action( "save_post", "save_recipe_embed", 10, 3 );