What are the consequences of ignoring the order of header commands and output in PHP?

Ignoring the order of header commands and output in PHP can lead to errors such as "headers already sent" or unexpected behavior in the output. To solve this issue, make sure to call header functions before any output is sent to the browser. 

<?php
ob_start(); // Start output buffering

// Place header commands before any output
header('Content-Type: text/html');

// Output content
echo 'Hello, world!';

ob_end_flush(); // Flush output buffer
?>

Keywords

header output buffering Content-Type ob_start headers already sent

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