I was working yesturday in PHP and came across an interesting problem and it took some time to figure out what was going on.
I had a system that was doing ajax calls to back-ends to show results on web pages. And the system has a php file to be included, that took care of opening config files and open database and stuff. And I needed to have one other file included to add some code in some places.
So the code was (in i_db.php):
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if (file_exists('inc/incdb.php')) { include('inc/incdb.php'); } |
Not to complicated. But now all my ajax backends (that also included this file – the i_db.php file) started to fail. And the error code was that firefix could not Parse the XML. The error message was:
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XML Parsing Error: XML or text declaration not at start of entity Location |
And this was shown in firebug console. Where did this come from?
Well after spending almost 2 hours trying to figure out of it was the include or if one could use require or what to do I finally came across the answer.
If you end a php file in “?>” and add an extra space after the > php will add an extra new line automatically.
I am not sure why or if it even is well documented anywhere but that’s what it does and removing that solved my problem.