Get Author's name outside Loop in WordPress

Get Author's name outside Loop in WordPress.php

<?php
    global $post;
    $author_id=$post->post_author;

	// echo gettype( $author_id );
	// echo "<pre>";
	// print_r( $author_id );
	// echo "</pre>";

	// https://codex.wordpress.org/Function_Reference/the_author_meta

	// Get Author's name outside Loop in WordPress.php
	// https://gist.github.com/thagxt/9955244
     
  	echo " - ";
    the_author_meta( 'display_name', $author_id );
?>
     
     
use it in your header:
     
<?php global $post; $author_id=$post->post_author; ?>
<meta name="author" content="<?php if(is_single()) { the_author_meta( 'nickname', $author_id ); } else { echo 'Something else'; } ?>">