[RESOLVED] header error

[sssphp]

I have some code that works fine until I add a header command. The code is:

if ($_SERVER['QUERY_STRING'] == NULL) {
print "No Query String";
}

When I change it to:

if ($_SERVER['QUERY_STRING'] == NULL) {
header( "Location: http://mysite.com" );
exit;
}

I get the following error if the condition is met:

Warning: Cannot modify header information - headers already sent by (output started at /[filepath]:12) in /[filepath] on [header line]

[edwardsbc]

Headers must be transmitted before any page rendered output. The error message is telling you some output has already been sent (and where, line 12). You can get around this if you turn on output buffering, or perhaps just by re-arranging your script's logic.

[sssphp]

Ahh....thanks.