.text文件中的Javascript

I have a Javascript function to get the client side date as follows:

var d = new Date();

var month = d.getMonth() + 1;

var thedate =
d.getDate() + "/" +
month + "/" + 
d.getFullYear() +
"  at  "
+ d.getHours() + ":" + 
(d.getMinutes()<10?'0':'') + d.getMinutes();


document.write(thedate);

I need this in PHP though, so I tried using this:

$datevar = '
<script>
var d = new Date();
var month = d.getMonth() + 1;
var thedate = d.getDate() + "/" + month + "/" + d.getFullYear() + "  at  " + d.getHours() + ":" + d.getMinutes();
document.write(thedate);
</script>
';

The piece of code above works fine, BUT only if I echo it. I don't want to echo the code. I want to insert it into a log file. This is my code for the log file:

$log_file_name = '1.log'; 
file_put_contents("$log_file_name, $datevar"  , FILE_APPEND);

This returns with literally the code in the log, not the date and time. I would like it to come up with the date.

Can I make it clear that I want the client's date, not the server's

Please, can someone help me with this. I will accept any alternative way to get the client's current date and time. Thank you in advance.

</div>

You need to get the client's time from the browser, then send that to the server with your form submit by adding the value to a hidden input.

HTML:

<input type="hidden" id="timestamp" name="timestamp" value="" />

Your JS will look like this:

<script>
var d = new Date();
document.getElementById("timestamp").value = d.getTime() / 1000;
</script>

Your time.php file will look like this:

<?php

if (!empty($_POST['timestamp'])) {
    $datevar = date('d/m/Y', $_POST['timestamp']) . ' at ' . date('h:i', $_POST['timestamp']) . PHP_EOL;
    $log_file_name = '1.log';
    file_put_contents($log_file_name, $datevar, FILE_APPEND);
}