$('#submit').on('click', function (e) {
        e.stopPropagation();
        $.ajax({
            url: "../../controllers/Controller.php",
            data: {
                action: "LoginController/login",
                username: username,
                password: password
            },
            dataType: "text",
            type: 'POST',
            timeout: 10000,
            error: function () {
                alert("服务器超时");
            },
            success: function (data) {
                    alert(data);
            }
        });
    });

<?php

if (!empty($_REQUEST['action'])) {
    try {
        $action = explode('/', $_REQUEST['action']);
        $class_name = $action[0];
        $method_name = $action[1];
        require $class_name . '.php';
        $class = new ReflectionClass($class_name);
        if (class_exists($class_name)) {
            if ($class->hasMethod($method_name)) {
                $func = $class->getmethod($method_name);
                $instance = $class->newInstance();
                $func->invokeArgs($instance, array($_REQUEST));
                $result = $instance->getResult();
                echo $result;
            }
        }
    } catch (Exception $exc) {
        echo $exc->getTraceAsString();
    }
}
?>

<?php

class LoginController {
　　
private $result;
function LoginController() {
        //初始化数据库连接等参数

    }

    function login($args) {
       //具体的登录逻辑
    }

    function getResult() {
        return $this->result;
    }

}

?>