here is the complete code for this php file:
<?php
header("content-type:text/html;charset=utf-8");
date_default_timezone_set("PRC");
$file="123.txt";
$msgs=[];
//
if (file_exists($file)){
$string=file_get_contents($file); //
if (strlen($string)>0){ //
$msgs=unserialize($string); //
};
};
//
if (isset($_POST["subpop"])){
$username=($_POST["username"]);
$title=strip_tags($_POST["title"]);
$content=strip_tags($_POST["content"]);
$time=time();
$data=compact("username","title","content","time");
array_push($msgs,$data);/*
Warning: array_push() expects parameter 1 to be array, null given in / on line 20
*/
$msgs=serialize($msgs); //
if(file_put_contents($file,$msgs)){ //$msgs
echo "<script>alert("");</script>";
}else {
echo "<script>alert("");</script>";
};
};
?>
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport"
content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<link href="https://stackpath.bootstrapcdn.com/bootstrap/4.1.1/css/bootstrap.min.css" rel="stylesheet" crossorigin="anonymous">
<script type="text/javascript" src="http://www.francescomalagrino.com/BootstrapPageGenerator/3/js/jquery-2.0.0.min.js"></script>
<script type="text/javascript" src="http://www.francescomalagrino.com/BootstrapPageGenerator/3/js/bootstrap.min.js"></script>
<title>Document</title>
<style>
.Dcenter{
position: fixed;
bottom: 0;
}
</style>
</head>
<body>
<?php if(is_array($msgs)&&count($msgs)>0):?>
<table cellspacing="0" cellpadding="0" width="70%" class="table table-sm table-bordered">
<tr>
<th>:</th>
<th>:</th>
<th>:</th>
<th>:</th>
</tr>
<tbody>
<?php $i=1;foreach($msgs as $val):?>
<tr class="success">
<td>
<?php echo $iPP;?>
</td>
<td>
<?php echo $val["username"];?>
</td>
<td>
<?php echo $val["title"];?>
</td>
<td>
<?php echo date("m/d/Y H:i:s",$val["time"]);?>
</td>
<td>
<?php echo $val["content"];?>
</td>
</tr>
<?php endforeach;?>
</tbody>
</table>
<?php endif;?>
<div class="container">
<div class="row Dcenter">
<form action="-sharp" method="post">
<fieldset>
<legend></legend>
<label>:</label><input type="text" name="username" placeholder="" required>
<label>:</label><input type="text" name="title" placeholder="" required>
<label>:</label><textarea name="content" rows="1"></textarea>
<input type="submit" name="subpop" value="">
</fieldset>
</form>
</div>
</div>
</body>
</html>