在costum post type wordpress中创建开始日期和结束日期

Question

我在costum post type wordpress中尝试此代码，但我发现错误..如何修复它？

function uep_add_event_info_metabox() {
    add_meta_box(
        'uep-event-info-metabox',
        __( 'Event Info', 'uep' ),
        'uep_render_event_info_metabox',
        'event',
        'side',
        'core'
    );
}
add_action( 'add_meta_boxes', 'uep_add_event_info_metabox' );

    function uep_render_event_info_metabox( $post ) {

    // generate a nonce field
    wp_nonce_field( basename( __FILE__ ), 'uep-event-info-nonce' );

    // get previously saved meta values (if any)
    $event_start_date = get_post_meta( $post->ID, 'event-start-date', true );
    $event_end_date = get_post_meta( $post->ID, 'event-end-date', true );
    $event_venue = get_post_meta( $post->ID, 'event-venue', true );

    // if there is previously saved value then retrieve it, else set it to the current time
    $event_start_date = ! empty( $event_start_date ) ? $event_start_date : time();

    //we assume that if the end date is not present, event ends on the same day
    $event_end_date = ! empty( $event_end_date ) ? $event_end_date : $event_start_date;

    ?>

<label for="uep-event-start-date"><?php _e( 'Event Start Date:', 'uep' ); ?></label>
        <input class="widefat uep-event-date-input" id="uep-event-start-date" type="text" name="uep-event-start-date" placeholder="Format: February 18, 2014" value="<?php echo date( 'F d, Y', $event_start_date ); ?>" />

<label for="uep-event-end-date"><?php _e( 'Event End Date:', 'uep' ); ?></label>
        <input class="widefat uep-event-date-input" id="uep-event-end-date" type="text" name="uep-event-end-date" placeholder="Format: February 18, 2014" value="<?php echo date( 'F d, Y', $event_end_date ); ?>" />

<label for="uep-event-venue"><?php _e( 'Event Venue:', 'uep' ); ?></label>
        <input class="widefat" id="uep-event-venue" type="text" name="uep-event-venue" placeholder="eg. Times Square" value="<?php echo $event_venue; ?>" />

    <?php <br ?>}