How to handle multiple file upload using PHP

Question

I want to upload files using PHP but the problem is that I don't know how many files I will upload.

My question is how can I upload files if I use file[]?

<form action="upload.php" method="post" enctype="multipart/form-data">
<label for="file">Filename:</label><input type="file" name="file[]" id="file" /> 
<br />
<label for="file">Filename:</label><input type="file" name="file[]" id="file" /> 
<br />
<input type="submit" name="submit" value="Submit" />
</form>

I will add just File box and I will use JavaScript to create more file input to upload but how to handle them in PHP?

Answer 1

See: $_FILES, Handling file uploads

<?php
    if(isset($_FILES['file']['tmp_name']))
    {
        // Number of uploaded files
        $num_files = count($_FILES['file']['tmp_name']);

        /** loop through the array of files ***/
        for($i=0; $i < $num_files;$i++)
        {
            // check if there is a file in the array
            if(!is_uploaded_file($_FILES['file']['tmp_name'][$i]))
            {
                $messages[] = 'No file uploaded';
            }
            else
            {
                // copy the file to the specified dir 
                if(@copy($_FILES['file']['tmp_name'][$i],$upload_dir.'/'.$_FILES['file']['name'][$i]))
                {
                    /*** give praise and thanks to the php gods ***/
                    $messages[] = $_FILES['file']['name'][$i].' uploaded';
                }
                else
                {
                    /*** an error message ***/
                    $messages[] = 'Uploading '.$_FILES['file']['name'][$i].' Failed';
                }
            }
        }
    }
?>