JS判断鼠标从什么方向进入一个容器（转）

方向反馈

/***********************以上是jquery代码，下面是原生js**********************/

var wrap = document.getElementById('wrap');
var hoverDir = function(e){
var w=wrap.offsetWidth;
var h=wrap.offsetHeight;
var x=(e.clientX - wrap.offsetLeft - (w / 2)) * (w > h ? (h / w) : 1);
var y=(e.clientY - wrap.offsetTop - (h / 2)) * (h > w ? (w / h) : 1);
var direction = Math.round((((Math.atan2(y, x) * (180 / Math.PI)) + 180) / 90) + 3) % 4;
var eventType = e.type;
var dirName = new Array('上方','右侧','下方','左侧');
if(e.type == 'mouseover' || e.type == 'mouseenter'){
wrap.innerHTML=dirName[direction]+'进入';
}else{
wrap.innerHTML=dirName[direction]+'离开';
}
}
if(window.addEventListener){
wrap.addEventListener('mouseover',hoverDir,false);
wrap.addEventListener('mouseout',hoverDir,false);
}else if(window.attachEvent){
wrap.attachEvent('onmouseenter',hoverDir);
wrap.attachEvent('onmouseleave',hoverDir);
}

转载于:https://www.cnblogs.com/syj-student/p/4046242.html