switch

switch ($_POST['storage_folder']) {

case "1": $storage_folder = "./smokovec"; break;
case "2": $storage_folder = "./strbskepleso"; break;
case "3": $storage_folder = "./lomnica"; break;
default : die("Nesprávne vybratá zložka"); break;
}

<?php
class Upload{


var $storage_folder = './files';


var $site_url       = 'http://xxx/upload/.$storage_folder.';   
var $sidens_navn = 'Sidens_navn';
var $filesize_limit = 104857600;

var $allowed_extensions = array('jpg','jpeg','pjpeg');
var $allowed_file_types = array('image/jpg','image/jpeg','image/pjpeg');         
 
 
var $filename;
var $file_content;
var $filesize_actual;

//pokračovanie kódu...

?>

<?php

class Upload{


var $storage_folder = 'files';     
var $sidens_navn = 'Sidens_navn';
var $filesize_limit = 104857600;

var $allowed_extensions = array('jpg','jpeg','pjpeg');
var $allowed_file_types = array('image/jpg','image/jpeg','image/pjpeg');         
 
 
var $filename;
var $file_content;
var $filesize_actual;

function site_url ($storage_folder)
{   
   switch ($storage_folder) {
   
   case "1":
      $storage_folder .= "/smokovec";
   break;
   case "2":
      $storage_folder .= "/strbskepleso";
   break;
   case "3":
      $storage_folder .= "/lomnica";
   break;
   default :
      die("Nesprávne vybratá zložka");
   break;
   }
   
   return 'http://xxx/upload/'.$storage_folder;
}
//pokračovanie kódu...
}

?>

$u = new Upload;
$u->site_url($_POST['storage_folder']);
// a tak dalej

<?php
class Upload{

var $storage_folder = "./files";

var $site_url       = 'http://xxx/upload/files';   
var $sidens_navn = 'Sidens_navn';
var $filesize_limit = 104857600;

var $allowed_extensions = array('jpg','jpeg','pjpeg');
var $allowed_file_types = array('image/jpg','image/jpeg','image/pjpeg');         
 
 
var $filename;
var $file_content;
var $filesize_actual;
var $filetype_actual;
var $password;
var $filelink;
var $message;
var $show_error;

function Upload(){
$this->message = '';
$this->filelink = '';
$this->load_error ='';
$this->show_error = false;

if (!$_FILES){
$this->showview();
}else{
   
$this->filename = $_FILES['myfile']['name'];
$this->file_content = $_FILES['myfile']['tmp_name'];
$this->filesize_actual = $_FILES['myfile']['size'];
$this->filetype_actual = strtolower($_FILES['myfile']['type']);

if ($this->filesize_actual <= 0){
$this->show_error = true;
$this->message = 'Vennligst velg en fil ĺ laste opp';
$this->showview();   
}

if ($this->filesize_actual > $this->filesize_limit){
$this->show_error = true;
$this->message = '<img src="icon_feilmelding.png">Filen for stor!';
$this->showview();   

}

if (!in_array($this->filetype_actual, $this->allowed_file_types)){
$this->show_error = true;
$this->message = '<img src="icon_feilmelding.png">Filtypen er ikke lovlig';
$this->showview();   
}

$file_extension = end(explode('.',$this->filename));
if (!in_array($file_extension, $this->allowed_extensions) || $file_extension ==''){
$this->show_error = true;
$this->message = '<img src="icon_feilmelding.png">Filtypen er ikke lovlig';
$this->showview();   
}


if (!is_writeable($this->storage_folder)){
$this->show_error = true;
$this->message = '<img src="icon_feilmelding.png"><b>Mappen /files mĺ CHMODEs, gjřr dette řyeblikkelig!</b>';
$this->showview();   
}

$filename_random_code = $this->randomcode();
$filename_random = $this->storage_folder.'/'.$filename_random_code.'.'.$file_extension;
if (!move_uploaded_file($_FILES['myfile']['tmp_name'], $filename_random)) {
$this->show_error = true;
$this->message = 'Prřv igjen!';
$this->showview();
}else{
$this->filelink = $this->site_url.'/'.$filename_random_code.'.'.$file_extension;
$this->show_error = true;
$this->message = '<b>Direkte url</b><br><br>'.$this->filelink.'<br><br><b>Webside</b><br><p>&lt;img src="'.$this->filelink.'"/&gt;</p><b>Forum</b><br><br>[img]'.$this->filelink.'[/img]<br><br><b>Thumbnail</b><br><br><p><a href="'.$this->filelink.'" target="_blank" ><img src="'.$this->filelink.'" target="_blank" alt="Thumbnail" width="100" height="100" border="0" /></a><br><br><textarea><a href="'.$this->filelink.'" target="_blank" ><img src="'.$this->filelink.'"alt="Thumbnail" width="100" height="100" border="0" /></a></textarea>';
$this->showview();   
}


}
}


function showview(){


if ($this->show_error==true){


$load_error = '<font face="Verdana" size="1" color="#006699">'.$this->message.'</font>';
}

echo '<form action="index.php" method="post" enctype="multipart/form-data">
<input type="radio" name="storage_folder" value="strbskepleso" />&nbsp;<font color="#006699">Štrbské Pleso</font>
<input type="radio" name="storage_folder" value="lomnica" />&nbsp;<font color="#006699">Tatranská Lomnica</font>
<input type="radio" name="storage_folder" value="smokovec" />&nbsp<font color="#006699">Starý Smokovec</font>
 

<input name="myfile" type="file" size="25"/>
<input type="submit" width="114" height="21" value="upload" name="B1">';

      
die();

}
   
function randomcode() {
    $chars = "023456789";
    srand((double)microtime() * 1000000);
    $i = 0;
    $pass = '';

    while ($i <= 3) {
        $num = rand() % 33;
        $tmp = substr($chars,$num,1);
        $pass = $pass.$tmp;
        $i++;
    }

    return $pass;
}
}
?>