Capture ctrl/meta/shift key modifiers in "data" event.

[brianjenkins94]

As far as I can tell xterm.js does not offer a solution to detect key combinations with ctrl, meta or shift modifiers.

The Node.js process.stdin.on("keypress" event returns two variables: ch and key, per keypress:

ch: c
key: { sequence: 'c',
  name: 'c',
  ctrl: false,
  meta: false,
  shift: false }

for c

ch:
key{ sequence: '\u0003',
  name: 'c',
  ctrl: true,
  meta: false,
  shift: false }

for ctrl + c.

Is there a way to get the same sort of data from xterm.js? Is there a generally accepted workaround?

[Tyriar]

@brianjenkins94 you should be able to do this by recording the raw key events by hooking up this function and allowing all events to go through:

xterm.js/typings/xterm.d.ts

Lines 462 to 471 in 0b8c320

	/**
	* Attaches a custom key event handler which is run before keys are
	* processed, giving consumers of xterm.js ultimate control as to what keys
	* should be processed by the terminal and what keys should not.
	* @param customKeyEventHandler The custom KeyboardEvent handler to attach.
	* This is a function that takes a KeyboardEvent, allowing consumers to stop
	* propagation and/or prevent the default action. The function returns
	* whether the event should be processed by xterm.js.
	*/
	attachCustomKeyEventHandler(customKeyEventHandler: (event: KeyboardEvent) => boolean): void;