how to log in php file code example

Example 1: php store log in a text file

$log_content="This line is logged on 2020-08-14 09:55:00";
$myfile = fopen("log.txt", "a") or die("Unable to open file!");
fwrite($myfile, $log_content);
fclose($myfile);

Example 2: how to create a logfile in php?

<?php
//Something to write to txt log
$log  = "User: ".$_SERVER['REMOTE_ADDR'].' - '.date("F j, Y, g:i a").PHP_EOL.
        "Attempt: ".($result[0]['success']=='1'?'Success':'Failed').PHP_EOL.
        "User: ".$username.PHP_EOL.
        "-------------------------".PHP_EOL;

//Save string to log, use FILE_APPEND to append.
file_put_contents('./log_'.date("j.n.Y").'.log', $log, FILE_APPEND);