Javascript - Track mouse position
JavascriptJavascript Problem Overview
I am hoping to track the position of the mouse cursor, periodically every t mseconds. So essentially, when a page loads - this tracker should start and for (say) every 100 ms, I should get the new value of posX and posY and print it out in the form.
I tried the following code - but the values do not get refreshed - only the initial values of posX and posY show up in the form boxes. Any ideas on how I can get this up and running ?
<html>
<head>
<title> Track Mouse </title>
<script type="text/javascript">
function mouse_position()
{
var e = window.event;
var posX = e.clientX;
var posY = e.clientY;
document.Form1.posx.value = posX;
document.Form1.posy.value = posY;
var t = setTimeout(mouse_position,100);
}
</script>
</head>
<body onload="mouse_position()">
<form name="Form1">
POSX: <input type="text" name="posx"><br>
POSY: <input type="text" name="posy"><br>
</form>
</body>
</html>
Javascript Solutions
Solution 1 - Javascript
The mouse's position is reported on the event object received by a handler for the mousemove event, which you can attach to the window (the event bubbles):
(function() {
document.onmousemove = handleMouseMove;
function handleMouseMove(event) {
var eventDoc, doc, body;
event = event || window.event; // IE-ism
// If pageX/Y aren't available and clientX/Y are,
// calculate pageX/Y - logic taken from jQuery.
// (This is to support old IE)
if (event.pageX == null && event.clientX != null) {
eventDoc = (event.target && event.target.ownerDocument) || document;
doc = eventDoc.documentElement;
body = eventDoc.body;
event.pageX = event.clientX +
(doc && doc.scrollLeft || body && body.scrollLeft || 0) -
(doc && doc.clientLeft || body && body.clientLeft || 0);
event.pageY = event.clientY +
(doc && doc.scrollTop || body && body.scrollTop || 0) -
(doc && doc.clientTop || body && body.clientTop || 0 );
}
// Use event.pageX / event.pageY here
}
})();
(Note that the body of that if will only run on old IE.)
Example of the above in action - it draws dots as you drag your mouse over the page. (Tested on IE8, IE11, Firefox 30, Chrome 38.)
If you really need a timer-based solution, you combine this with some state variables:
(function() {
var mousePos;
document.onmousemove = handleMouseMove;
setInterval(getMousePosition, 100); // setInterval repeats every X ms
function handleMouseMove(event) {
var dot, eventDoc, doc, body, pageX, pageY;
event = event || window.event; // IE-ism
// If pageX/Y aren't available and clientX/Y are,
// calculate pageX/Y - logic taken from jQuery.
// (This is to support old IE)
if (event.pageX == null && event.clientX != null) {
eventDoc = (event.target && event.target.ownerDocument) || document;
doc = eventDoc.documentElement;
body = eventDoc.body;
event.pageX = event.clientX +
(doc && doc.scrollLeft || body && body.scrollLeft || 0) -
(doc && doc.clientLeft || body && body.clientLeft || 0);
event.pageY = event.clientY +
(doc && doc.scrollTop || body && body.scrollTop || 0) -
(doc && doc.clientTop || body && body.clientTop || 0 );
}
mousePos = {
x: event.pageX,
y: event.pageY
};
}
function getMousePosition() {
var pos = mousePos;
if (!pos) {
// We haven't seen any movement yet
}
else {
// Use pos.x and pos.y
}
}
})();
As far as I'm aware, you can't get the mouse position without having seen an event, something which this answer to another Stack Overflow question seems to confirm.
Side note: If you're going to do something every 100ms (10 times/second), try to keep the actual processing you do in that function very, very limited. That's a lot of work for the browser, particularly older Microsoft ones. Yes, on modern computers it doesn't seem like much, but there is a lot going on in browsers... So for example, you might keep track of the last position you processed and bail from the handler immediately if the position hasn't changed.
Solution 2 - Javascript
onmousemove = function(e){console.log("mouse location:", e.clientX, e.clientY)}
Open your console (Ctrl+Shift+J), copy-paste the code above and move your mouse on browser window.
Solution 3 - Javascript
Here's a solution, based on jQuery and a mouse event listener (which is far better than a regular polling) on the body:
$("body").mousemove(function(e) {
document.Form1.posx.value = e.pageX;
document.Form1.posy.value = e.pageY;
})
Solution 4 - Javascript
I believe that we are overthinking this,
function mouse_position(e)
{
//do stuff
}
<body onmousemove="mouse_position(event)"></body>
Solution 5 - Javascript
What I think that he only wants to know the X/Y positions of cursor than why answer is that complicated.
// Getting 'Info' div in js hands
var info = document.getElementById('info');
// Creating function that will tell the position of cursor
// PageX and PageY will getting position values and show them in P
function tellPos(p){
info.innerHTML = 'Position X : ' + p.pageX + '<br />Position Y : ' + p.pageY;
}
addEventListener('mousemove', tellPos, false);
* {
padding: 0:
margin: 0;
/*transition: 0.2s all ease;*/
}
#info {
position: absolute;
top: 10px;
right: 10px;
background-color: black;
color: white;
padding: 25px 50px;
}
<!DOCTYPE html>
<html>
<body>
<div id='info'></div>
</body>
</html>
Solution 6 - Javascript
ES6 based code:
let handleMousemove = (event) => {
console.log(`mouse position: ${event.x}:${event.y}`);
};
document.addEventListener('mousemove', handleMousemove);
If you need throttling for mousemoving, use this:
let handleMousemove = (event) => {
console.warn(`${event.x}:${event.y}\n`);
};
let throttle = (func, delay) => {
let prev = Date.now() - delay;
return (...args) => {
let current = Date.now();
if (current - prev >= delay) {
prev = current;
func.apply(null, args);
}
}
};
// let's handle mousemoving every 500ms only
document.addEventListener('mousemove', throttle(handleMousemove, 500));
here is example
Solution 7 - Javascript
Just a simplified version of @T.J. Crowder and @RegarBoy's answers.
Less is more in my opinion.
Check out onmousemove event for more info about the event.
There's a new value of posX and posY every time the mouse moves according to the horizontal and vertical coordinates.
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Example Mouse Tracker</title>
<style>
body {height: 3000px;}
.dot {width: 2px;height: 2px;background-color: black;position: absolute;}
</style>
</head>
<body>
<p>Mouse tracker</p>
<script>
onmousemove = function(e){
//Logging purposes
console.log("mouse location:", e.clientX, e.clientY);
//meat and potatoes of the snippet
var pos = e;
var dot;
dot = document.createElement('div');
dot.className = "dot";
dot.style.left = pos.x + "px";
dot.style.top = pos.y + "px";
document.body.appendChild(dot);
}
</script>
</body>
</html>
Solution 8 - Javascript
If just want to track the mouse movement visually:
<!DOCTYPE html>
<html>
<head>
<title></title>
</head>
<style type="text/css">
* { margin: 0; padding: 0; }
html, body { width: 100%; height: 100%; overflow: hidden; }
</style>
<body>
<canvas></canvas>
<script type="text/javascript">
var
canvas = document.querySelector('canvas'),
ctx = canvas.getContext('2d'),
beginPath = false;
canvas.width = window.innerWidth;
canvas.height = window.innerHeight;
document.body.addEventListener('mousemove', function (event) {
var x = event.clientX, y = event.clientY;
if (beginPath) {
ctx.lineTo(x, y);
ctx.stroke();
} else {
ctx.beginPath();
ctx.moveTo(x, y);
beginPath = true;
}
}, false);
</script>
</body>
</html>
Solution 9 - Javascript
document.addEventListener('mousemove', (event) => {
document.getElementById("line").style.top = event.clientY - 10 + 'px';
document.getElementById("lineY").style.left = event.clientX - 10 + 'px';
document.getElementById("pos").style.top = (event.clientY - 60) + 'px';
document.getElementById("pos").style.left = (event.clientX - 60) + 'px';
});
body {
position: relative;
height: auto;
min-height: 100% !important;
background-color: lightblue;
}
h1 {
color: white;
text-align: center;
}
p {
font-family: verdana;
font-size: 20px;
}
.abs {
position: relative;
}
.lineY {
display: flex;
position: relative;
left: 0px;
background-color: black;
width: 2px;
height: 100vh;
min-height: 100%
}
.line {
display: flex;
position: relative;
background-color: black;
min-height: 2px;
width: 100%;
}
.circle {
display: flex;
position: absolute;
left: 0px;
top: 0px;
}
<div class='line' id="line"></div>
<div class='lineY' id="lineY"></div>
<svg height="100" width="100" id="pos" class="circle">
<circle cx="50" cy="50" r="40" stroke="black" stroke-width="3" fill="transparent" />
</svg>
Solution 10 - Javascript
Irrespective of the browser, below lines worked for me to fetch correct mouse position.
event.clientX - event.currentTarget.getBoundingClientRect().left event.clientY - event.currentTarget.getBoundingClientRect().top
Solution 11 - Javascript
I don't have enough reputation to post a comment reply, but took TJ Crowder's excellent answer and fully defined the code on a 100ms timer. (He left some details to the imagination.)
Thanks OP for the question, and TJ for the answer! You're both a great help. Code is embedded below as a mirror of isbin.
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Example</title>
<style>
body {
height: 3000px;
}
.dot {
width: 2px;
height: 2px;
background-color: black;
position: absolute;
}
</style>
</head>
<body>
<script>
(function() {
"use strict";
var mousePos;
document.onmousemove = handleMouseMove;
setInterval(getMousePosition, 100); // setInterval repeats every X ms
function handleMouseMove(event) {
var eventDoc, doc, body;
event = event || window.event; // IE-ism
// If pageX/Y aren't available and clientX/Y are,
// calculate pageX/Y - logic taken from jQuery.
// (This is to support old IE)
if (event.pageX == null && event.clientX != null) {
eventDoc = (event.target && event.target.ownerDocument) || document;
doc = eventDoc.documentElement;
body = eventDoc.body;
event.pageX = event.clientX +
(doc && doc.scrollLeft || body && body.scrollLeft || 0) -
(doc && doc.clientLeft || body && body.clientLeft || 0);
event.pageY = event.clientY +
(doc && doc.scrollTop || body && body.scrollTop || 0) -
(doc && doc.clientTop || body && body.clientTop || 0 );
}
mousePos = {
x: event.pageX,
y: event.pageY
};
}
function getMousePosition() {
var pos = mousePos;
if (!pos) {
// We haven't seen any movement yet, so don't add a duplicate dot
}
else {
// Use pos.x and pos.y
// Add a dot to follow the cursor
var dot;
dot = document.createElement('div');
dot.className = "dot";
dot.style.left = pos.x + "px";
dot.style.top = pos.y + "px";
document.body.appendChild(dot);
}
}
})();
</script>
</body>
</html>
Solution 12 - Javascript
Here is a solution
document.onmousemove = showCoords;
function showCoords(event) {
var x = event.clientX;
var y = event.clientY;
var coords = "X coords: " + x + ", Y coords: " + y;
document.getElementById("box1").innerHTML = coords;
}
Solution 13 - Javascript
if anyone still looking for answer then,
function track(e) {
console.log("X - ", e.pageX, " Y - ", e.pageY);
}
addEventListener("mousemove", track, false);
paste this code in console to see immediate action
Solution 14 - Javascript
Here’s a combination of the two requirements: track the mouse position, every 100 milliseconds:
var period = 100,
tracking;
window.addEventListener("mousemove", function(e) {
if (!tracking) {
return;
}
console.log("mouse location:", e.clientX, e.clientY)
schedule();
});
schedule();
function schedule() {
tracking = false;
setTimeout(function() {
tracking = true;
}, period);
}
This tracks & acts on the mouse position, but only every period milliseconds.
Solution 15 - Javascript
Here is the simplest way to track your mouse position
Html
<body id="mouse-position" ></body>
js
document.querySelector('#mouse-position').addEventListener('mousemove', (e) => {
console.log("mouse move X: ", e.clientX);
console.log("mouse move X: ", e.screenX);
}, );
Solution 16 - Javascript
We recently had to find the current x,y position to enumerate elements over which the cursor is hovering independent of z-index. We ended up just attaching a mousemove event listener to document e.g.,
function findElements(e) {
var els = document.elementsFromPoint(e.clientX, e.clientY);
// do cool stuff with els
console.log(els);
return;
}
document.addEventListener("mousemove", findElements);
Solution 17 - Javascript
This is the shortest way to get the coordinates of mouse pointer. Just put your element where cursor is going to hover, inside $("")
$("***enter you element here***").mousemove(function(event)
{
console.clear()
var x = event.originalEvent.screenX;
var y = event.originalEvent.screenY;
console.log("x : "+x)
console.log("y : "+y)
})
Solution 18 - Javascript
[...document.querySelectorAll("*")].forEach(h => h.addEventListener("mousemove", function(event) {
console.table({
"mouse x": event.clientX,
"mouse y": event.clientY
});
}));