public static function getInstance()
 {
     if (self::$instance == null) {
         self::$instance = new GoodsBrandProvider();
     }
     return self::$instance;
 }
<?php

include_once "../../common.php";
require_once DATACONTROL . '/BMManage/IsLogin.php';
require_once DATACONTROL . '/BMManage/GoodsBrandProvider.php';
require_once DATAMODEL . '/BMManage/GoodsBrandMDL.php';
if (isset($_POST["method"])) {
    $methods = $_POST["method"];
} else {
    if (isset($_GET["method"])) {
        $methods = $_GET["method"];
    } else {
        exit;
    }
}
switch ($methods) {
    case "List":
        $listResult = GoodsBrandProvider::getInstance()->ListAll($_GET["lv"], $_GET["type3Id"]);
        echo json_encode($listResult);
        break;
    case "Add":
        $addResult = GoodsBrandProvider::getInstance()->AddGoodsBrand($_POST["name"], $_POST["order"]);
        echo json_encode($addResult);
        break;
    case "edit":
        $editResult = GoodsBrandProvider::getInstance()->updateGoodsBrand($_POST["id"], $_POST["name"], $_POST["order"], $_POST["state"]);
        echo json_encode($editResult);
        break;
}