What are some best practices for troubleshooting and resolving the issue of headers already sent in PHP?

Headers already sent in PHP typically occur when there is whitespace or output before the header() function is called. To resolve this issue, ensure that no whitespace or output is sent before calling the header() function. 

<?php
ob_start(); // Start output buffering
// Your PHP code here

// Check for headers already sent
if (headers_sent()) {
    // Output an error message or redirect
    die("Headers already sent");
}

// Set headers
header("Location: https://www.example.com");
ob_end_flush(); // Flush output buffer
?>

Keywords

output buffering ob_start ob_clean error_reporting ini_set

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