Wrong (maxTouchPoints) and ('ontouchstart' in document) in Chrome mobile emulation mode

问题

I use a touchscreen device detection like this:

if (window.navigator.maxTouchPoints || 'ontouchstart' in document)  
    // handle as mobile device
else
    // handle as desktop

When I change the screen in Chrome mobile emulation the result of both maxTouchPoints and 'ontouchstart' in document is unpredictable.

For one and same emulated screen it may return maxTouchPoints equals to 0 or 1, and 'ontouchstart' in document equals to true or false.

So, I cannot really on this check.
Could you recommend a way to fix this?

回答1:

How about this?

function isTouchscreen() {
  return ("ontouchstart" in window) || (navigator.maxTouchPoints > 0) ? true : false;
}

if (isTouchscreen()) {
  console.log('IS touchscreen');}
else {
  console.log('IS NOT touchscreen');
}

Reference: https://developer.mozilla.org/en-US/docs/Web/API/Navigator/maxTouchPoints

来源：https://stackoverflow.com/questions/55833326/wrong-maxtouchpoints-and-ontouchstart-in-document-in-chrome-mobile-emulati