Question

I’m folowing this tutorial to create php/jquery based chat application.

In short, this code puts message to log:

<?  
session_start();  
if(isset($_SESSION['name'])){  
    $text = $_POST['text'];  

    $fp = fopen("log.html", 'a');  
    fwrite($fp, "<div class='msgln'>(".date("g:i A").") <b>".$_SESSION['name']."</b>: ".stripslashes(htmlspecialchars($text))."<br></div>");  
    fclose($fp);  
}  
?>  

And this line of code displays log

function loadLog(){       

        $.ajax({  
            url: "log.html",  
            cache: false,  
            success: function(html){  
                $("#chatbox").html(html); //Insert chat log into the #chatbox div  
            },  
        });  
    }  

Log is just simple HTML document.

How could I limit log to display only last 100 messages? And that log doesn’t get too big? ( over 1 MB )

Answer 1

The following should be what you want:

$lines = file('log.html');

// get line number 2 - 100
if(count($lines) > 100) $lines = array_slice(1, 99);

// convert newlines to <br/> and append
$lines[] = 
   nl2br("<div class='msgln'>(".date("g:i A").") <b>".$_SESSION['name']."</b>: ".stripslashes(htmlspecialchars($text))."<br></div>");

file_put_contents('log.html', join("\n", $lines));