輸出緩衝中介軟體讓您可以切換兩種輸出緩衝模式：附加（預設）和提前模式。 附加模式會使用現有的回應本文附加內容。 提前模式會建立新的回應本文物件，並將內容提前加入到現有回應本文的輸出的開頭。此中介軟體應放在中介軟體堆疊的中心，以便它最後執行。
<?php
use Slim\Factory\AppFactory;
use Slim\Middleware\OutputBufferingMiddleware;
use Slim\Psr7\Factory\StreamFactory;
require __DIR__ . '/../vendor/autoload.php';
$app = AppFactory::create();
$streamFactory = new StreamFactory();
/**
* The two modes available are
* OutputBufferingMiddleware::APPEND (default mode) - Appends to existing response body
* OutputBufferingMiddleware::PREPEND - Creates entirely new response body
*/
$mode = OutputBufferingMiddleware::APPEND;
$outputBufferingMiddleware = new OutputBufferingMiddleware($streamFactory, $mode);
$app->add($outputBufferingMiddleware);
// ...
$app->run();