CodeIgniter没有看到来自valum的ajax文件上传器的参数

I'm using the Valums AJAX file uploader with CodeIgniter 2.1.0. When I try to pass parameters to my ajax controller, nothing seems to get passed.

function initializeAttachmentUploader(obj) {
    element = document.getElementById(obj);

    var uploader = new qq.FileUploader({
        multiple: true,
        element: element,
        action: '<?php echo site_url('ajax/attachment_upload'); ?>/' + $('#token').val(),
        debug: true,
        params: { test: 'dsfasdfasdfasdf' },
    });
}

And in the ajax attachment_upload function

$param = $this->input->get('test');

Always comes up as NULL. I'm using CodeIgniter, allow_get_array is TRUE. I have also tried:

$param = $this->input->post('test');

No errors, other than it's just NULL. What might I be doing wrong here?

You'll have to enable query string for that to work.

$config['enable_query_strings'] = TRUE;

From the documentation:

Please note: If you are using query strings you will have to build your own URLs, rather than utilizing the URL helpers (and other helpers that generate URLs, like some of the form helpers) as these are designed to work with segment based URLs.