警告：session_start()：无法发送会话 cookie - 标头已由（但：本地主机上没有错误）发送

Question

我希望有人能帮助我解决这个有线问题。我的计算机上没有问题（Mac 上带有 XAMPP 的 localhost），但在我的虚拟主机上，我收到以下错误消息：

Warning: session_start(): Cannot send session cookie - headers already sent by...

我知道这个错误可能是由于调用之前的一些输出，但我想知道我是否可以在网络服务器或其他地方更改我的 PHP.ini (?) 上的某些内容以使其正常工作。

谢谢！
蒂姆

Answer 1

这是写在php.ini 中的。很有趣...

; Output buffering is a mechanism for controlling how much output data
; (excluding headers and cookies) PHP should keep internally before pushing that
; data to the client. If your application's output exceeds this setting, PHP
; will send that data in chunks of roughly the size you specify.
; Turning on this setting and managing its maximum buffer size can yield some
; interesting side-effects depending on your application and web server.
; You may be able to send headers and cookies after you've already sent output
; through print or echo. You also may see performance benefits if your server is
; emitting less packets due to buffered output versus PHP streaming the output
; as it gets it. On production servers, 4096 bytes is a good setting for performance
; reasons.
; Note: Output buffering can also be controlled via Output Buffering Control
;   functions.
; Possible Values:
;   On = Enabled and buffer is unlimited. (Use with caution)
;   Off = Disabled
;   Integer = Enables the buffer and sets its maximum size in bytes.
; Note: This directive is hardcoded to Off for the CLI SAPI
; Default Value: Off
; Development Value: 4096
; Production Value: 4096
; http://php.net/output-buffering
output_buffering=4096

Answer 2

在您的php.ini 中，您可以为此将output_buffering 转为On。这应该可以防止标头发送错误，这样您的会话就不会失败。