Clear clipboard to prohibit unauthorised copying, insert message?

Question

Is it possible to write your own message into the clipboard when copying website data using ctrl+c? I\'ve found some Javascript that clears the clipboard - would be interest

Answer 1

Yes, you can. The basic trick is that you detect when a user holds down Control, and select a different piece of text on the page.

Answer 2

You could place the following:

$( document ).ready(function() {
    if (event.ctrlKey && event.keyCode == 67) {
        var inputFieldClear = document.createElement("input");
        inputFieldClear.setAttribute("value", "Insert Default Value Here");
        document.body.appendChild(inputFieldClear);
        inputFieldClear.select();
        document.execCommand('copy');
        inputFieldClear.remove();
        console.log("Attempting to Alter Clipboard")
}});

That would work in something like TamperMonkey - not sure if it could be incorporated into the sites source or not.

Hope it helps! :)

Answer 3

You can't do it purely through JavaScript.

JavaScript editing of the clipboard is considered a security vulnerability (and there is much more discussion on this).

You could do it through hacks that uses Flash for clipboard access interacting with JavaScript.