非觸屏端支持的點擊事件屬性:
onmousedown();
onmousemove();
onmouseup();
觸屏端支持的點擊事件屬性:
ontouchstart();
ontouchmove();
ontouchend();
所以只需判斷是否支持ontouchstart()屬性,即可分辨設備是觸屏端還是非觸屏端
function listenToUser(canvas) {
//判斷是手機還是電腦,就看其支不支持觸屏,即是否有 ontouchstart 屬性,這個就叫特性檢測
if (document.body.ontouchstart !== undefined) {
//觸屏設備
//1.在觸屏點一下
canvas.ontouchstart = function () {}
//2.手指在觸屏上移動
canvas.ontouchmove = function () {}
//3.手機離開觸屏
canvas.ontouchend = function () {}
}else{
//非觸屏設備
//1.鼠標點擊
canvas.onmousedown = function () {}
//2.按住鼠標不鬆開移動
canvas.onmousemove = function () {}
//3.鬆開鼠標
canvas.onmouseup = function () {}
}