Question

I’m new php, It’s learning process.

I’ve a html upload form. I’m trying to rename the uploaded file. So Following is php code that get the file extension and after that i add a php uniqid(); to rename it.

Get file extension code:

$img = $_FILES['images']['name'];

function getExtension($str)
{
     $i = strrpos($str,".");
     if (!$i) { return ""; } 

     $l = strlen($str) - $i;
     $ext = substr($str,$i+1,$l);
     return $ext;
}

$extension =  getExtension($img);
$id = uniqid();
$newimg = $id.'.'.$extension;

Well, this OK for me for only one upload file, BUT if I’ve multiple upload form then how do i get multiple files extension with this function?

For get the multiple files following is my php code:

$uploaded_files = array();
$upload_directory = dirname(__file__) . '/uploaded/'; //set upload directory    


for ($i = 0; $i < count($_FILES['images']['name']); $i++)
            {
                $number_of_file_fields++;

                if ($_FILES['images']['name'][$i] != '')
                { //check if file field empty or not
                    $number_of_uploaded_files++;

$uploaded_files[] = $_FILES['images']['name'][$i];

if (move_uploaded_file($_FILES['images']['tmp_name'][$i], $upload_directory .   $_FILES['images']['name'][$i]))
                    {
                        $number_of_moved_files++;
                    }

                }

            }

Html Form

<table width="1020" border="0" cellspacing="7" cellpadding="0">   
<tr>
 <td valign="top" width="250">
     Upload your property picture
 </td>
 <td>
    <div id="file_container">
        <input name="images[]" type="file" class="tr2"  />
        <br />
    </div>
 <a href="javascript:void(0);" onClick="add_file_field();">Add another</a>
 <input type="submit" value="Save & Continue" name="Submit" class="submit" />
 </td>  
</tr> 
</table>

Answer 1

function changeFilename($str)
{
     $pathinfo = pathinfo($str);
     return uniqid() . "." . $pathinfo['extension'];
}
$oldarray = array("hello.txt","ytuwe.php");
$newarray = array_map("changeFilename", $oldarray);
var_dump($newarray);

Here is a demonstration: http://ideone.com/gPi61D