[jquery] multiple key press handler +

[jquery] multiple key press handler +

related sololearn Q&A

This is just a basic example of how handle multiple keys press with JQuery...

Below pseudo-buttons will reflect the states of some keys:

As we are listening for keys events for whole document, in code playground app and web context, we need to set focus to the inner document (the iframe holding your playground output, to avoid the need of user touch/click the iframe... (see JQuery .ready() method in JS source)