我已经读了几十篇关于这个错误的帖子，但我仍然不明白。因此，我想补充一下关于ajax 400的讨论。这是一个插件，用于显示/验证/记录一个名为shortcode的简单表单。

根插件文件如下所示：

    add_menu_page( 
        \'Able Signup\',                //  page title
        \'Able Signup\',                //  menu title
        \'manage_options\',             //  capability (role of who can use)
        \'able_signup\',                //  menu slug
        \'able_signups\',               //  function in .php app that gets called when clicking
        \'dashicons-clipboard\',        //  icon
        4                             //  position in menu
    ); 
    require_once ( "apps/view_signups.php");  //for later dump of DB
    require_once ( \'apps/save_signups.php\' ); //process submitted form <== ??? 
}
add_action( \'admin_menu\', \'wpdocs_register_able_signup_menu_page\' );

// starting of a shortcode
function able_show_form_template( $atts ) {
    require_once ( \'apps/form_signups.php\' );

    ob_start();
    able_display_form_template( $atts ); //name of function called 
    return ob_get_clean();
}
add_shortcode( \'add_signup_form\', \'able_show_form_template\' ); // [add_signup_form id=\'01\']
?>

表单页面上的ajax如下所示：

$j(\'#signup\').on(\'submit\', function(){
    //console.log("submit fired"); //works
    //console.log("ajax_url"); //set in functions.php and works
    $j.ajax({
        type: \'POST\',
        url: ajax_url,
        data: {
            action:     \'save-form\',
            full_name:  $j(\'#full_name\').val(),
            //more data
        },
        success: function (response) {
            //stuff
        }
    });
    return false;
});

最后，调用PHP文件进行处理：

// in apps/save_signups.php
function save_form() {
    if ( wp_verify_nonce( $_POST[\'signup_nonce\'], \'\' ) ) {
    
       //process form
    
        wp_send_json( $messages );
        wp_die();
    } else {
        wp_send_json( "Bad form" );
    }
}
add_action( \'wp_ajax_save_form\', \'save_form\' );
add_action( \'wp_ajax_nopriv_save_form\', \'save_form\' );

Apache错误。日志显示了这一点，但没有多大意义：

ndefined offset: 0 in /var/www/susites/abledesignbuild/htdocs/wp-includes/class-wp-query.php on line 3284\'

我错过了什么？我唯一能想到的是save_signups.php 不是“；参见；但不知道怎么说。

谢谢布拉德

add_action( \'wp_ajax_save_form\', \'save_form\' );
add_action( \'wp_ajax_nopriv_save_form\', \'save_form\' );

action:     \'save-form\'

action:     \'save_form\'

     require_once ( \'apps/save_signups.php\' ); //process submitted form <== ??? 
}
add_action( \'admin_menu\', \'wpdocs_register_able_signup_menu_page\' );