如果鼠标在屏幕外，则隐藏移动的 div（不仅要跟踪鼠标何时离开屏幕）[重复]

Question

这是我在 js 中的代码：

        window.onload = function(){
            var bsDiv = document.getElementById("box");
            var x, y;
// On mousemove use event.clientX and event.clientY to set the location of the div to the location of the cursor:
            window.addEventListener('mousemove', function(event){
                x = event.clientX;
                y = event.clientY;                    
                if ( typeof x !== 'undefined' ){
                    bsDiv.style.left = x + "px";
                    bsDiv.style.top = y + "px";
                }
            }, false);
        }
    </script>

我想添加一个函数，如果光标不在屏幕上（或位置为空？）它使元素不可见，然后在光标重新输入时使其重新可见

Answer 1

document.onmouseout在鼠标离开屏幕时触发。

所以做类似的事情

function invisible(div){
    div.style.visibility = 'hidden';
}
document.addEventListener(onmouseout, invisible(divName), true);