php實現上傳文件並解壓

<?php

//上傳RAR壓縮包並解壓
//獲取當前文件
$dir=getcwd();

if(isset($_POST['sub'])){
    $tname=$_FILES['upfiles']['tmp_name'];
    $nname=$_FILES['upfiles']['name'];

    move_uploaded_file($tname,$nname);

    $obj=new COM('Wscript.Shell');
    //執行doc解壓命令
    $obj->run('winrar x $dir\\".$nname." ".$dir,1,true');
    //刪除上傳的文件
    unlink($nname);
}

?>

<form action='index.php' method="post" enctype="multipart/form-data">
    <input type="file" name="upfiles">
    <input type="submit" name="sub" value="上傳並解壓">
</form>