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PHP
<?php
include "connection.php";
include "header.php";
 ?>

 <!DOCTYPE html>
<html>
<head>
	<title>Feedback</title>
    <link rel="stylesheet" type="text/css" href="style2.css">
	<meta charset="utf-8">
	<meta name="viewport" content="width=device-width,initial scale=1">
	<!-- <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.4.1/css/bootstrap.min.css">

<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.4.1/jquery.min.js"></script>


<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.4.1/js/bootstrap.min.js"></script> -->

<!-- <header>
	<div class="logo">
	<img src="img/m.png" style="margin-top: -79px;">
	<h1 style="color: yellow;">LIBRARY MANAGEMENT SYSTEM</h1>
</div>
</header> -->
<br>

<style type="text/css">
	.wrapper
	{
		padding: 10px;
		margin: 5px auto;
width: 600px;
height: 400px;
background-color: #9e9e9e;
opacity: .6;
color: black;
	}
	.form-control{
      height: 100px;
      width: 60%;
	}
	.scroll{
		width: 100%;
		height: 300px;
		overflow: auto;
	}
	.section{
    height: 450px;
    width: 1361px;
   /* background-color:grey ;*/
}
	 .sect_img
	{
	padding-left: 20px;
    height: 400px;
    width: 50%;
    margin-left: 338px;
    margin-top: 0px;
     background-image: url("img/t.jpg");
}
.footer{
    height: 80px;
    width:1361;
    background-color: #009688; 
}
</style>
</head>
<body>
<br><br>
<section>
	<div class="sect_img">
	<div class="wrapper">
		<br><br>
<!-- <h4>If you have any suggestions or questions  please comment below:</h4> -->
<!-- <form style="" action="" method="post">
	<input class="form-control" type="text" name="comment" placeholder="write something...">
	<br><br>
	<input class="btn btn-default" type="submit" name="submit" value="comment" style="width: 100px; height: 30px;"> 
</form> -->
<div class="scroll">
<?php 
if(isset($_POST['submit']))
{
$sql="INSERT INTO `comments` VALUES('','$_POST[comment]');";
if(mysqli_query($db,$sql))
{
	$q="SELECT * FROM `comments` ORDER BY `id`,`comment` DESC";
	$res=mysqli_query($db,$q);

	echo "<table class='table table_bordered'>";
	while ($row=mysqli_fetch_assoc($res))
	{
      echo "<tr>";
        echo "<td>"; echo $row['comment']; echo "</td>";
        echo "</tr>";
	}
  }
}
else
{
$q="SELECT * FROM `comments` ORDER BY `id`,`comment` DESC";
	$res=mysqli_query($db,$q);

	echo "<table class='table table_bordered'>";
	while ($row=mysqli_fetch_assoc($res))
	{
      echo "<tr>";
        echo "<td>"; echo $row['comment']; echo "</td>";
        echo "</tr>";
    }

}
 ?>

</div>

</div>

</section>

</body>
</html>
Source

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