I want to be able to have a trigger on keypress for %. So far, I have this:
$(iframeDocument).find('body').on('keydown', function(event) { if (event.which == 53) { alert("% pressed"); } }); But, it will also trigger when I press "5". How can I differentiate between the two?
You can use shiftKey property in the event object to check if the SHIFT is pressed when the event occurred.
var keyCode = event.which || event.keyCode; if (event.shiftKey && keyCode === 53) { // Shift key is pressed console.log('% pressed'); } 
Use event.key. It's visible on the demo in the jQuery documentation for .keydown().
$(iframeDocument).find('body').on('keydown', function(event) { if (event.key === '%') { console.log(event.key + ' pressed'); } }); If the pressed key has a printed representation, the returned value is a non-empty Unicode character string containing the printable representation of the key.
Just so you're aware, this property is not completely cross-browser compatible. See caniuse for a comprehensive list of supported and unsupported browsers.
If you're curious to mess around and see what values it yields, try this demo (it uses React just for fun):
class Label extends React.Component { static keydownListener(event) { this.setState({ label: event.key }); } constructor() { super(); this.state = { label: 'Press any key' }; this.listener = Label.keydownListener.bind(this); window.addEventListener('keydown', this.listener); } componentWillUnmount() { window.removeEventListener('keydown', this.listener); } render() { return ( <div>{this.state.label}</div> ); } } ReactDOM.render(<Label />, document.body); window.focus();html, body { width: 100%; height: 100%; padding: 0; margin: 0; display: flex; align-items: center; justify-content: center; }<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script> <script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>
event.which, surely? There's also an event.keyCode which appears to be an equivalent. But I don't find an event.key when debugging a keyDown event handler.