check the extensions and allow only those that you want.

get the extension
PHP Code: 
$ext substr($filenamestrrpos($filename'.') + 1); 
allow only pdf and excel
PHP Code: 
$allowed = array('pdf','xsl');
if(
in_array($ext,$allowed)) upload(); 
your code (not tested)
PHP Code: 
<?php

    error_reporting
(E_ALL);
 
    
/*** the upload directory ***/
    
$upload_dir'uploads';

    
/*** numver of files to upload ***/
    
$num_uploads 5;

    
/*** maximum filesize allowed in bytes ***/
    
$max_file_size  5120000000;
 
    
/*** the maximum filesize from php.ini ***/
    
$ini_max str_replace('M'''ini_get('upload_max_filesize'));
    
$upload_max $ini_max 1024;

    
/*** a message for users ***/
    
$msg 'Please select files for uploading';

    
/*** an array to hold messages ***/
    
$messages = array();
    
    
//allowed extensions
    
$allowed = array('pdf','xls');

    
/*** check if a file has been submitted ***/
    
if(isset($_FILES['userfile']['tmp_name']))
    {
        
/** loop through the array of files ***/
        
for($i=0$i count($_FILES['userfile']['tmp_name']);$i++)
        {
            
$filename basename($_FILES['userfile']['name'][$i]);
            
$ext substr($filenamestrrpos($filename'.') + 1);
            if(
in_array($ext,$allowed)) {
                
// check if there is a file in the array
                
if(!is_uploaded_file($_FILES['userfile']['tmp_name'][$i]))
                {
                    
$messages[] = 'No file uploaded';
                }
                
/*** check if the file is less then the max php.ini size ***/
                
elseif($_FILES['userfile']['size'][$i] > $upload_max)
                {
                    
$messages[] = "File size exceeds $upload_max php.ini limit";
                }
                
// check the file is less than the maximum file size
                
elseif($_FILES['userfile']['size'][$i] > $max_file_size)
                {
                    
$messages[] = "File size exceeds $max_file_size limit";
                }
                else
                {
                    
// copy the file to the specified dir 
                    
if(@copy($_FILES['userfile']['tmp_name'][$i],$upload_dir.'/'.$_FILES['userfile']['name'][$i]))
                    {
                        
/*** give praise and thanks to the php gods ***/
                        
$messages[] = $_FILES['userfile']['name'][$i].' uploaded';
                    }
                    else
                    {
                        
/*** an error message ***/
                        
$messages[] = 'Uploading '.$_FILES['userfile']['name'][$i].' Failed';
                    }
                }
            }
            else {
                
$messages[] = 'Uploading '.$_FILES['userfile']['name'][$i].' Failed. Extension not allowed.';
            }
        }
    }
?>
 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
 "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
 <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
 <head>
 <title>Multiple File Upload</title>
 </head>

 <body>
 
 <h3><?php echo $msg?></h3>
 <p>
 <?php
    
if(sizeof($messages) != 0)
    {
        foreach(
$messages as $err)
        {
            echo 
$err.'<br />';
        }
    }
 
?>
 </p>
 <form enctype="multipart/form-data" action="<?php echo htmlentities($_SERVER['PHP_SELF']);?>" method="post">
 <input type="hidden" name="MAX_FILE_SIZE" value="<?php echo $max_file_size?>" />
 <?php
    $num 
0;
    while(
$num $num_uploads)
    {
        echo 
'<div><input name="userfile[]" type="file" /></div>';
        
$num++;
    }
 
?>

 <input type="submit" value="Upload" />
 </form>

 </body>
 </html>
t3od0r Reviewed by t3od0r on . how add file extension for upload files Dear sir, PDF and excel extension is we only want to allow other files is not allow please help me.. <?php error_reporting(E_ALL); Rating: 5