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PHP Build a Simple PHP Application Adding a Contact Form Working with Get Variables

Zack Klinger
Zack Klinger
17,622 Points
Posted by Zack Klinger
Zack Klinger
17,622 Points

Warning: Cannot modify header information - headers already sent by (output... [SOLVED]

Warning: Cannot modify header information - headers already sent by (output started at /Applications/MAMP/htdocs/contact.php:2) in /Applications/MAMP/htdocs/contact.php on line 5

in this code:

<!-- this takes the information from the POST method and puts it into a variable called &email_body and then sends the user to the contact.php page with status=thanks. --> <?php error_reporting(-1); ini_set('display_errors','On'); ... header("Location: contact.php?status=thanks"); ...

Is failing because of the HTML call in my comments sections happening before header() is called.

source: http://stackoverflow.com/questions/8028957/how-to-fix-headers-already-sent-error-in-php

"" No output before sending headers!

Functions that send/modify HTTP headers must be invoked before any output is made. summary ⇊ Otherwise the call fails:

Warning: Cannot modify header information - headers already sent (output started at script:line) Some functions modifying the HTTP header are:

header / header_remove session_start / session_regenerate_id setcookie / setrawcookie Output can be:

Unintentional:

Whitespace before <?php or after ?> The UTF-8 Byte Order Mark specifically Previous error messages or notices ""

Zack Klinger
Zack Klinger
17,622 Points
Zack Klinger
Zack Klinger
17,622 Points

That's funny, it ignored the !-- in my first post. If you call !-- (an HTML comment) before your PHP code, the header() function cannot be invoked.