Yii2 报错 Headers already sent in
有时候我们把Yii2 版本进行升级之后 会报一些莫名其妙的错误，这次就遇到如下错误信息
an Error occurred while handling another error:
exception
'yii\web\HeadersAlreadySentException' with message 'Headers already sent in /xxxx/xxxx/xxx.php on line 90.' in /xxxx/xxxx/vendor/yiisoft/yii2/web/Response.php:366
Stack trace:
#0 /xxxx/xxxx/vendor/yiisoft/yii2/web/Response.php(339): yii\web\Response->sendHeaders()
#1 /xxxx/xxxx/vendor/yiisoft/yii2/web/ErrorHandler.php(135): yii\web\Response->send()
#2/xxxx/xxxx/vendor/yiisoft/yii2/base/ErrorHandler.php(111):
yii\web\ErrorHandler->renderException(Object(yii\web\HeadersAlreadySentException))
#3 [internal function]: yii\base\ErrorHandler->handleException(Object(yii\web\HeadersAlreadySentException))
#4 {main}查阅了一些资料说，是因为使用json输出内容的时候 没有exit。以前的写法如下
protected function renderJSON($data=[], $msg ="ok", $code = 200)
{
header('Content-type: application/json');
echo json_encode([
"code" => $code,
"msg" => $msg,
"data" => $data,
"req_id" => $this->geneReqId(),
]);
return Yii::$app->end();
}改成如下
protected function renderJSON($data=[], $msg ="ok", $code = 200)
{
$response = Yii::$app->response;
$response->format = Response::FORMAT_JSON;
$response->data = [
"code" => $code,
"msg" => $msg,
"data" => $data,
"req_id" => $this->geneReqId(),
];
return $response;
}原文地址：Yii2 报错 Headers already sent in
标签：yii2 json header