//20190123新增加全局API数据返回接口，统一规定，-1：未登录，0：普通错误，1：返回成功
function ajaxmsg($msg = "", $status = 1, $data = '', $errcode = '')
{
    $json['msg'] = $msg;
    $json['status'] = $status;
    $json['data'] = $data;
    if ($errcode) {
        $json['errcode'] = $errcode;
    }
    echo json_encode($json, true);
    exit;
}