先上效果图
附上代码
<!DOCTYPE html>
<html lang="en"><head><meta charset="UTF-8" /><meta http-equiv="X-UA-Compatible" content="IE=edge" /><meta name="viewport" content="width=device-width, initial-scale=1.0" /><title>Document</title><style>.four {width: 200px;height: 100px;background-color: #00f;position: relative;}</style>
</head><body><div class="four" style="top:0;left:0"></div><script>var div = document.getElementsByTagName('div')[0];function drag() {var disX,disY;div.addEventListener('mousedown', function (e) {var e = e || window.event;disX = e.pageX - parseInt(div.style.left);disY = e.pageY - parseInt(div.style.top);document.addEventListener('mousemove', move);document.addEventListener('mouseup', function (e) {document.removeEventListener('mousemove', move);})})function move(e) {var e = e || window.event;div.style.left = (e.pageX - disX) + 'px';div.style.top = e.pageY - disY + 'px';}}drag()</script>
</body></html>
![[iOS]从拾遗到Runtime(上)](https://img-blog.csdnimg.cn/direct/ecdc6b1172bd44518e275f37c6844f24.png)
