如何在模板中使用此meta box函数？ （WordPress）

Question

这是我的功能：

$prefix = 'dbt_';

$meta_box = array(
    'id' => 'my-meta-box',
    'title' => 'Custom meta box',
    'page' => 'post',
    'context' => 'normal',
    'priority' => 'high',
    'fields' => array(
        array(
            'name' => 'Checkbox',
            'id' => $prefix . 'checkbox',
            'type' => 'checkbox'
        )
    )
);

add_action('admin_menu', 'mytheme_add_box');

// Add meta box
function mytheme_add_box() {
    global $meta_box;

    add_meta_box($meta_box['id'], $meta_box['title'], 'mytheme_show_box', $meta_box['page'], $meta_box['context'], $meta_box['priority']);
}

// Callback function to show fields in meta box
function mytheme_show_box() {
    global $meta_box, $post;

    // Use nonce for verification
    echo '<input type="hidden" name="mytheme_meta_box_nonce" value="', wp_create_nonce(basename(__FILE__)), '" />';

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

    foreach ($meta_box['fields'] as $field) {
        // get current post meta data
        $meta = get_post_meta($post->ID, $field['id'], true);

        echo '<tr>',
                '<th style="width:20%"><label for="', $field['id'], '">', $field['name'], '</label></th>',
                '<td>';
        switch ($field['type']) {
            case 'checkbox':
                echo '<input type="checkbox" name="', $field['id'], '" id="', $field['id'], '"', $meta ? ' checked="checked"' : '', ' />';
                break;
        }
        echo    '<td>',
            '</tr>';
    }

    echo '</table>';
}

add_action('save_post', 'mytheme_save_data');

// Save data from meta box
function mytheme_save_data($post_id) {
    global $meta_box;

    // verify nonce
    if (!wp_verify_nonce($_POST['mytheme_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;
    }

    foreach ($meta_box['fields'] as $field) {
        $old = get_post_meta($post_id, $field['id'], true);
        $new = $_POST[$field['id']];

        if ($new && $new != $old) {
            update_post_meta($post_id, $field['id'], $new);
        } elseif ('' == $new && $old) {
            delete_post_meta($post_id, $field['id'], $old);
        }
    }
}

如果选中复选框，我会尝试在模板中使用此代码：

<?php if ($meta_box = get_post_meta($post->ID, "checkbox", true) ) : ?>
Show this when checkbox checked
<?php endif; ?>

而且它不起作用

Answer 1

您现在应该已经有了答案，但是此行应该为您提供线索：

'id' => $prefix . 'checkbox'

因此，将您的if语句更改为：

$meta_box = get_post_meta($post->ID, dbt_checkbox, true) 

应该可以帮到你。

Answer 2

只需尝试此代码

<?php
add_action( 'admin_init', 'my_admin_samplepost' );
function my_admin_samplepost() {
    add_meta_box( 'samplepost_meta_box', 'Car Details', 'display_samplepost_meta_box','samplepost', 'normal', 'high' );
}
function display_samplepost_meta_box( $samplepost ) {
    ?>
    <h4>General Details</h4>
    <table width="100%">
        <tr>
            <td style="width: 25%">Monthly Paymeny</td>
            <td><input type="text" style="width:425px;" name="meta[payment]" value="<?php echo esc_html( get_post_meta( $samplepost->ID, 'payment', true ) );?>" />
            </td>
        </tr>
        <tr>
            <td>Price ($)</td>
            <td><input type="text" style="width:425px;" name="meta[price]" placeholder="$" value="<?php echo esc_html( get_post_meta( $samplepost->ID, 'price', true ) );?>" />
            </td>
        </tr>
        <tr>
            <td>Milage</td>
            <td><input type="text" style="width:425px;" name="meta[milage]" value="<?php echo esc_html( get_post_meta( $samplepost->ID, 'milage', true ) );?>" />
            </td>
        </tr>
    </table>
<?php 
}
add_action( 'save_post', 'add_samplepost_fields', 10, 2 );
function add_samplepost_fields( $samplepost_id, $samplepost ) {
    if ( $samplepost->post_type == 'samplepost' ) {
        if ( isset( $_POST['meta'] ) ) {
            foreach( $_POST['meta'] as $key => $value ){
                update_post_meta( $samplepost_id, $key, $value );
            }
        }
    }
}