<?php 

$site_name = $_SERVER['HTTP_HOST']; 
$url_dir = "http://".$_SERVER['HTTP_HOST'].dirname($_SERVER['PHP_SELF']); 
$url_this =  "http://".$_SERVER['HTTP_HOST'].$_SERVER['PHP_SELF']; 

$upload_dir = "images/avatars/"; 
$upload_url = $url_dir."/images/avatars/"; 
$message =""; 



if ($_FILES['userfile']) { 
  $message = do_upload($upload_dir, $upload_url); 
} 
else { 
  $message = "Invalid File Specified."; 
} 

print $message; 

function do_upload($upload_dir, $upload_url) { 

  $temp_name = $_FILES['userfile']['tmp_name']; 
  $file_name = $_FILES['userfile']['name']; 
  $file_type = $_FILES['userfile']['type']; 
  $file_size = $_FILES['userfile']['size']; 
  $result    = $_FILES['userfile']['error']; 
  $file_url  = $upload_url.$file_name; 
  $file_path = $upload_dir.$file_name; 

  //File Name Check 
   if ( $file_name =="") { 
      $message = "Invalid File Name Specified"; 
      return $message; 
   } 
   //File Size Check 
   else if ( $file_size > 50000000000000000000000000000) { 
       $message = "The file size is over 500K."; 
       return $message; 
   } 


   $result  =  move_uploaded_file($temp_name, $file_path); 
   $message = ($result)?"File url <a href=$file_url.>$file_url</a>" : 
            "Somthing is wrong with uploading a file."; 

   return $message; 
} 

?> 
<form name="upload" id="upload" ENCTYPE="multipart/form-data" method="post"> 
 Upload Image<input type="file" id="userfile" name="userfile"> 
 <input type="submit" name="upload" value="Upload"> 
</form>