<input type="button" id="btn" value="点我">
<script>
var btn = document.getElementById("btn");
btn.addEventListener("mousedown",function(){
console.log("my button mousedown");
});
btn.addEventListener("click",function(){
console.log("my button click");
});
btn.addEventListener("mouseup",function(){
console.log("my button mouseup");
});
</script>
//执行顺序
onmousedown > onmouseup > click