offset:相对于当前“盒子”的距离 ，与滚动条无关
client:相对于可视区域的距离，与滚动条无关
page:相对于整个页面的距离，与滚动条有关
示例代码：
1 <!DOCTYPE html> 2 <html lang="en"> 3 <head> 4 <meta charset="UTF-8"> 5 <title>Title</title> 6 <style> 7 * { 8 margin: 0; 9 padding: 0; 10 } 11 12 #div1 { 13 width: 400px; 14 height: 1400px; 15 background-color: red; 16 } 17 18 #div2 { 19 width: 400px; 20 height: 1400px; 21 background-color: green; 22 } 23 </style> 24 </head> 25 <body> 26 <div id="div1"></div> 27 <div id="div2"></div> 28 <script src="main.js"></script> 29 </body> 30 </html>
1 (function () { 2 3 function objClick(targetId) { 4 document.getElementById(targetId).onclick = function (e) { 5 console.log("offsetX " + e.offsetX + " offsetY " + e.offsetY); 6 console.log("clientX " + e.clientX + " clientY " + e.clientY); 7 console.log("pageX " + e.pageX + " pageY " + e.pageY); 8 console.log(""); 9 } 10 } 11 12 objClick("div1"); 13 objClick("div2"); 14 15 16 })();