实现鼠标左键拖拽效果的两种方式：
方式一：
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <title>Document</title> <style> .move { width: 100px; height: 100px; background: red; border-radius: 50%; position:absolute; left:0; top:0; } </style> </head> <body> <div class="move"> </div> <script> //制作一个鼠标左键拖拽效果 var div = document.getElementsByClassName("move")[0]; var style = window.getComputedStyle(div); var divLeft = parseFloat(style.left); var divTop = parseFloat(style.top); div.onmousedown = function(e){ if(e.button !== 0){ return ;//不是鼠标左键，return } window.onmousemove = function(e){ divLeft += e.movementX;//距上次鼠标位置的X长度 divTop += e.movementY;//距上次鼠标位置的Y长度 div.style.left = divLeft + "px"; div.style.top = divTop + "px"; } window.onmouseup = window.onmouseleave = function(){ if(e.button === 0){//鼠标左键 window.onmousemove = null; } } } </script> </body> </html>
方式二：
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <title>Document</title> <style> .move { width: 100px; height: 100px; background: red; border-radius: 50%; position:absolute; left:0; top:0; } </style> </head> <body> <div class="move"> </div> <script> //制作一个鼠标左键拖拽效果 var div = document.getElementsByClassName("move")[0]; var style = window.getComputedStyle(div); div.onmousedown = function(e){ if(e.button !== 0){ return ;//不是鼠标左键，return } var divLeft = parseFloat(style.left); var divTop = parseFloat(style.top); var divPageX = e.pageX; var divPageY = e.pageY; window.onmousemove = function(e){ var disX = e.pageX - divPageX; var disY = e.pageY - divPageY; div.style.left = divLeft + disX + "px"; div.style.top = divTop + disY + "px"; } window.onmouseup = window.onmouseleave = function(){ if(e.button === 0){//鼠标左键 window.onmousemove = null; } } } </script> </body> </html>
原文：https://www.cnblogs.com/lanshanxiao/p/12778804.html
