Escap XSS attack and face deformation when uploading file in php - php

Question

I have a form that users can upload files like html, css, php, java, js, txt, javascript and other files which i included
But my problem is how can i prevent xss attack or face deformation after successful upload
Example when user upload files like this
<input type='text'> //This will show input instead of in plain text
body{display:none!important;} // My document body off
So i tried to make this php script, it worked very fine while viewing in my site but when i try to open the file in my notepadd++ i don't like the look can anyone suggest me how i can do this better outside my code or fix mine
<?php
session_start();
if(!class_exists('DBController')){ require_once("../../_inc/dbcontroller.php"); }
if(isset($_FILES['fileuploader'])){
include_once('../fileextension.php');
$test = true;
$FileName = $_FILES['fileuploader']['name'];
$tmp_name = $_FILES['fileuploader']['tmp_name'];
$uploadPath = __DIR__ . '/'.$FileName;
$currentBas = '';
$defaultProjecName = '';
$exetype = pathinfo($FileName, PATHINFO_EXTENSION);
$extension = strtolower($exetype);
if(in_array($extension,$afile)){
$FTypeof = 'file';
}
else if(in_array($extension,$aimg)){
$FTypeof = 'image';
}
else{
$FTypeof = 'unknown';
}
$FDiscripT = 'No available '.($FTypeof == 'unknown') ? '' : $FTypeof.' discription';
//Here i move the selected file in a directory
$moveResult = move_uploaded_file($tmp_name, $uploadPath);
if ($moveResult != true) {
unlink($uploadPath);
}else{
// If file was moved then open file and get the content
if(file_exists($uploadPath)){
$fileUploadname = $uploadPath;
$filechecker = fopen($fileUploadname, "a+");
$mesure = filesize($fileUploadname);
if($mesure == 0){
$sizechecker = 1;
}
else{
$sizechecker = filesize($fileUploadname);
}
$get_content_file = fread($filechecker, $sizechecker);
fclose($filechecker);
//Then here i use htmlentities to encote the file content
if(!empty($get_content_file)){
$sanitize_file = htmlentities($get_content_file);
$sanitize_file_status = true;
}
if($sanitize_file_status == true){
//Now i put the content back the the file
try{
$openForWrite = fopen($uploadPath, 'w');
$recreateNewfile = fwrite($openForWrite, $sanitize_file);
fclose($openForWrite);
if($recreateNewfile){
//Then insert the other information to database
if($test == false){
$makefile_db = new DBController();
$makefile_db->prepare("INSERT INTO jailorgchild(jailowner,jailchildbasname,prodefault,jailchillink,jailchilddate,filediscription,contentType)
VALUES(:jailowner,:jailchildbasname,:SubDif,:jailchillink,:jailchilddate,:FDiscripT,:contentType)");
$makefile_db->bind(':jailchildbasname', $currentBas);
$makefile_db->bind(':SubDif', $defaultProjecName);
$makefile_db->bind(':jailchillink', $FileName);
$makefile_db->bind(':jailowner', $_SESSION['username']);
$makefile_db->bind(':jailchilddate', date('Y-m-d H:i:s'));
$makefile_db->bind(':FDiscripT', $FDiscripT);
$makefile_db->bind(':contentType', $FTypeof);
$makefile_db->execute();
$filewasmake = $makefile_db->rowCount();
$makefile_db->free();
}
echo '<pre>';
echo $sanitize_file;
//echo 'Unclean Content <br/>'. $get_content_file;
}
}catch(PDOException $e){
echo "Error:" . $e->getMessage();
}
}else{
unlink($uploadPath);
}
}
}
}
?>
HTML FORM
<form method="post" action="testuploader.php" enctype="multipart/form-data">
<input type="file" name="fileuploader">
<input type="submit" value="load">
</form>
OUTPUT IN NOTEPAD++
<?php if(isset($_GET['postid'])){ echo '<h5 style="color:
#2f2f2f;">Related Articles</h5><br/>'; <?php } }?>
So if another user download it and the file look like that i don't think is good please i need help