Javascript获取当前鼠标在元素内的坐标
转载自：https://jingyan.baidu.com/article/c1a3101e5a32b3de656debbd.html
doctype html>
<html>
<head>
<meta charset="utf-8">
<title>获取鼠标在Canvas中的坐标位置title>
<style>
body{text-align: center;}
#canvas {
border: 1px solid #ccc;
width: 300px;
height: 300px;
overflow: hidden;
margin: 0 auto;
}
style>
head>
<body>
<div id="tips">div>
<div id="canvas" onmousemove="get_canvas(event,this)" onclick="test(event);">div>
body>
html>
<script>
function get_canvas(ev, obj) {
m_clientX = ev.clientX - obj.offsetLeft;
m_clientY = ev.clientY - obj.offsetTop;
// clientX/Y 鼠标相对当前页面body可视区域左上角的坐标
// offsetLeft/Top 元素左上角相对父元素左上角的距离
document.getElementById("tips").innerHTML = "当前坐标：X：" + m_clientX + " ,Y：" + m_clientY;
}
script>