<!DOCTYPE html> <html> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>简单拖曵原理实例</title> <style type="text/css"> #drag{ width:400px; height:300px; cursor:move; position:absolute; top:100px; left:100px; border:solid 1px #ccc; } h2{ color:red; height:80px; line-height:80px; margin:0; } </style> <script src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js" type="text/javascript"></script> <script type="text/javascript"> $(function(){ /*--------------拖曳效果---------------- *原理：标记拖曳状态dragging ,坐标位置iX, iY * mousedown:fn(){dragging = true, 记录起始坐标位置，设置鼠标捕获} * mouseover:fn(){判断如果dragging = true, 则当前坐标位置 - 记录起始坐标位置，绝对定位的元素获得差值} * mouseup:fn(){dragging = false, 释放鼠标捕获，防止冒泡} */ var dragging = false; var iX, iY; $("#drag").mousedown(function(e) { dragging = true; iX = e.clientX - this.offsetLeft; iY = e.clientY - this.offsetTop; this.setCapture && this.setCapture(); return false; }); document.onmousemove = function(e) { if (dragging) { var e = e || window.event; var oX = e.clientX - iX; var oY = e.clientY - iY; $("#drag").css({"left":oX + "px", "top":oY + "px"}); return false; } }; $(document).mouseup(function(e) { dragging = false; $("#drag")[0].releaseCapture(); e.cancelBubble = true; }) }) </script> </head> <body> <div id="drag"> <h2>来拖动我啊</h2> </div> </body> </html>