网页如何确定用户是否有鼠标或触摸屏输入？

Question

If I have a webpage coded in html5 and javascript how can it detect what kind of input hardware the user has ? To give useful and correct instructions to them. A user may have mouse, touchscreen, both or full keyboard, limited keyboard on Smartphone ...etc.

Answer 1

I use this to avoid mouseover effects when I'm not sure.

    <script>
    var hasMouse = false;

    window.document.addEventListener('mouseover', mouseFound);

        function mouseFound() {
            hasMouse = true;
            window.document.removeEventListener('mouseover', mouseFound);
            console.log('found a mouse');
        }
    </script>