如何忽略php中的重定向错误

Question

I got this warning in php:

Cannot modify header information - headers already sent by (output started at

When I installed mysql, apache, and php separately but when I'm using Wamp the warning does not exist and the page redirects gracefully.

I have already tried setting the error reporting to only display errors and not warnings and what happened is that the warning didn't show up but the page also didn't redirect.

I know this is already considered bad practice but my code base has a lot of these codes and modifying them all might introduce new bugs to the code. Is there any way to completely ignore this warning in php?

Answer 1

The classic way to avoid - and not ignore - this problem is with output buffering, ob_start() and ob_flush(). Start the buffering before any output, and finish with the flush explicitly, or it may do so automatically. This captures any output rather than printing it, and so any headers that are output are done so before any visible content.

Fixing the bug of things being output, from the filename you had in the error message is the best way to fix this though. Removing the closing '?>' from files when it's not needed might help.