Upload Many Files

<?php
if(isset($_FILES['files'])){
    $errors= array();
 foreach($_FILES['files']['tmp_name'] as $key => $tmp_name ){
  $file_name = $key.$_FILES['files']['name'][$key];
  $file_size =$_FILES['files']['size'][$key];
  $file_tmp =$_FILES['files']['tmp_name'][$key];
  $file_type=$_FILES['files']['type'][$key];
        if($file_size > 2097152){
   $errors[]='File size must be less than 2 MB';
        }  

        $desired_dir="user_data";

        if(empty($errors)==true){
            if(is_dir($desired_dir)==false){
                mkdir("$desired_dir", 0700);  // Create directory if it does not exist
            }
            if(is_dir("$desired_dir/".$file_name)==false){
                move_uploaded_file($file_tmp,"$desired_dir/".$file_name);
            }else{         // rename the file if another one exist
                $new_dir="$desired_dir/".$file_name.time();
                 rename($file_tmp,$new_dir) ;  
            }
  
        }else{
                print_r($errors);
        }
    }
 if(empty($error)){
  echo "Success";
 }
}
?>

<form action="" method="POST" enctype="multipart/form-data">
 <input type="file" name="files[]" multiple/>
 <input type="submit"/>
</form>

Source: