Clipboard

You can easily access the internal clipboard in TYPO3 from your backend modules:

Extension examples, file Classes/Controller/ModuleController.php
use TYPO3\CMS\Backend\Clipboard\Clipboard;
use TYPO3\CMS\Core\Utility\DebugUtility;
use TYPO3\CMS\Core\Utility\GeneralUtility;

class ModuleController extends ActionController implements LoggerAwareInterface
{
    protected function debugClipboard()
    {
        /** @var $clipboard Clipboard */
        $clipboard = GeneralUtility::makeInstance(Clipboard::class);
        // Read the clipboard content from the user session
        $clipboard->initializeClipboard();
        DebugUtility::debug($clipboard->clipData);
    }
}
Copied!

In this simple piece of code we instantiate a clipboard object and make it load its content. We then dump this content into the BE module's debug window, with the following result:

A dump of the clipboard in the debug window

This tells us what objects are registered on the default tab ("normal") (a content element with id 216 in "copy" mode) and the numeric tabs (which can each contain more than one element). It also tells us that the current tab is number 2. We can compare with the BE view of the clipboard:

The clipboard as seen in the backend

which indeed contains two files.

Clipboard content should not be accessed directly, but using the elFromTable() method of the clipboard object:

Extension examples, file Classes/Controller/ModuleController.php
use TYPO3\CMS\Backend\Clipboard\Clipboard;
use TYPO3\CMS\Core\Utility\GeneralUtility;

class ModuleController extends ActionController implements LoggerAwareInterface
{
    protected function getCurrentClipboard():array
    {
        /** @var $clipboard Clipboard */
        $clipboard = GeneralUtility::makeInstance(Clipboard::class);
        // Read the clipboard content from the user session
        $clipboard->initializeClipboard();
        // Access files and pages content of current pad
        $clipboardContent = [
            'files' => $clipboard->elFromTable('_FILE'),
            'pages' => $clipboard->elFromTable('pages'),
        ];
        return $clipboardContent;
    }
}
Copied!

Here we first try to get all files and then all page records on the current pad (which is pad 2). Then we change to the "Normal" pad, call the elFromTable() method again.

In the "examples" extension, this data is passed to a BE module view for display, which is really just information:

Clipboard items