function isModifierKey(oEvent) {
			var iKeyCode = oEvent.which; // jQuery oEvent.which normalizes oEvent.keyCode and oEvent.charCode

			return (iKeyCode === KeyCodes.SHIFT) ||
				(iKeyCode === KeyCodes.CONTROL) ||
				(iKeyCode === KeyCodes.ALT) ||
				(iKeyCode === KeyCodes.CAPS_LOCK) ||
				(iKeyCode === KeyCodes.NUM_LOCK);
		}
Detect whether the pressed key is a modifier.

Modifier keys are considered:
SHIFT, CONTROL, ALT, CAPS_LOCK, NUM_LOCK
These keys don't send characters, but modify the characters sent by other keys.

@param {jQuery.Event} oEvent The event object of the <code>keydown</code>, <code>keyup</code> or <code>keypress</code> events.
@static
@returns {boolean} True if a modifier key was pressed