代码：
<!DOCTYPE html> <html lang="zh-cn"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <meta content="width=device-width,initial-scale=1,minimum-scale=1,maximum-scale=1,user-scalable=no" /> <title>鼠标拖动小方块</title> <style type="text/css"> .lineDiv { position: relative; height: 5px; background: red; width: 300px; margin: 50px auto; } .lineDiv .minDiv { position: absolute; top: -5px; left: 0; width: 15px; height: 15px; background: green; cursor: pointer } .lineDiv .minDiv .vals { position: absolute; font-size: 20px; top: -45px; left: -10px; width: 35px; height: 35px; line-height: 35px; text-align: center; background: blue; } .lineDiv .minDiv .vals:after { content: ""; width: 0px; height: 0px; border-top: 6px solid blue; border-left: 6px solid transparent; border-right: 6px solid transparent; border-bottom: 6px solid transparent; display: block; margin-left: 11px; } </style> </head> <body> <center> <h3>用鼠标拖动小方块<span>0</span>%</h3> </center> <div> <div> <div>0</div> </div> </div> <script> window.onload = function() { var lineDiv = document.getElementById('lineDiv'); //长线条 var minDiv = document.getElementById('minDiv'); //小方块 var msg = document.getElementById("msg"); var vals = document.getElementById("vals"); var ifBool = false; //判断鼠标是否按下 //鼠标按下方块 minDiv.addEventListener("touchstart", function(e) { e.stopPropagation(); ifBool = true; console.log("鼠标按下") }); //拖动 window.addEventListener("touchmove", function(e) { console.log("鼠标拖动") if(ifBool) { var x = e.touches[0].pageX || e.touches[0].clientX; //鼠标横坐标var x var lineDiv_left = getPosition(lineDiv).left; //长线条的横坐标 var minDiv_left = x - lineDiv_left; //小方块相对于父元素（长线条）的left值 if(minDiv_left >= lineDiv.offsetWidth - 15) { minDiv_left = lineDiv.offsetWidth - 15; } if(minDiv_left < 0) { minDiv_left = 0; } //设置拖动后小方块的left值 minDiv.style.left = minDiv_left + "px"; msg.innerText = parseInt((minDiv_left / (lineDiv.offsetWidth - 15)) * 100); vals.innerText = parseInt((minDiv_left / (lineDiv.offsetWidth - 15)) * 100); } }); //鼠标松开 window.addEventListener("touchend", function(e) { console.log("鼠标弹起") ifBool = false; }); //获取元素的绝对位置 function getPosition(node) { var left = node.offsetLeft; //获取元素相对于其父元素的left值var left var top = node.offsetTop; current = node.offsetParent; // 取得元素的offsetParent // 一直循环直到根元素 while(current != null) { left += current.offsetLeft; top += current.offsetTop; current = current.offsetParent; } return { "left": left, "top": top }; } } </script> </body> </html>