Posted By
Bajarangi soft ,
Posted On 05-10-2020
Create an Image Magnifier Glass
Step 1: Create index.html file and implement below code in it.
<div class="img-magnifier-container">
<img id="image" src="../image/demo4.jpg" width="600" height="400">
</div>
Step 2:Now we create css code for display button so implement below code in index.html file
The container must have a "relative" positioning.
<style>
* {box-sizing: border-box;}
.img-magnifier-container {
position:relative;
}
.img-magnifier-glass {
position: absolute;
border: 3px solid #000;
border-radius: 50%;
cursor: none;
/*Set the size of the magnifier glass:*/
width: 100px;
height: 100px;
}
</style>
<script>
function magnify(imgID, zoom) {
var img, glass, w, h, bw;
img = document.getElementById(imgID);
/*create magnifier glass:*/
glass = document.createElement("DIV");
glass.setAttribute("class", "img-magnifier-glass");
/*insert magnifier glass:*/
img.parentElement.insertBefore(glass, img);
/*set background properties for the magnifier glass:*/
glass.style.backgroundImage = "url('" + img.src + "')";
glass.style.backgroundRepeat = "no-repeat";
glass.style.backgroundSize = (img.width * zoom) + "px " + (img.height * zoom) + "px";
bw = 3;
w = glass.offsetWidth / 2;
h = glass.offsetHeight / 2;
/*execute a function when someone moves the magnifier glass over the image:*/
glass.addEventListener("mousemove", moveMagnifier);
img.addEventListener("mousemove", moveMagnifier);
/*and also for touch screens:*/
glass.addEventListener("touchmove", moveMagnifier);
img.addEventListener("touchmove", moveMagnifier);
function moveMagnifier(e) {
var pos, x, y;
/*prevent any other actions that may occur when moving over the image*/
e.preventDefault();
/*get the cursor's x and y positions:*/
pos = getCursorPos(e);
x = pos.x;
y = pos.y;
/*prevent the magnifier glass from being positioned outside the image:*/
if (x > img.width - (w / zoom)) {x = img.width - (w / zoom);}
if (x < w / zoom) {x = w / zoom;}
if (y > img.height - (h / zoom)) {y = img.height - (h / zoom);}
if (y < h / zoom) {y = h / zoom;}
/*set the position of the magnifier glass:*/
glass.style.left = (x - w) + "px";
glass.style.top = (y - h) + "px";
/*display what the magnifier glass "sees":*/
glass.style.backgroundPosition = "-" + ((x * zoom) - w + bw) + "px -" + ((y * zoom) - h + bw) + "px";
}
function getCursorPos(e) {
var a, x = 0, y = 0;
e = e || window.event;
/*get the x and y positions of the image:*/
a = img.getBoundingClientRect();
/*calculate the cursor's x and y coordinates, relative to the image:*/
x = e.pageX - a.left;
y = e.pageY - a.top;
/*consider any page scrolling:*/
x = x - window.pageXOffset;
y = y - window.pageYOffset;
return {x : x, y : y};
}
}
</script>
Step 4:Now Implement java script to Initiate the Magnify Function.
<script>
/* Initiate Magnify Function
with the id of the image, and the strength of the magnifier glass:*/
magnify("image", 3);
</script>
Complete Code For Creating Image Magnifier Glass Using JavaScript
<!DOCTYPE html>
<html>
<head>
<title>How To Create Image Magnifier Glass Using JavaScript</title>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.4.1/css/bootstrap.min.css">
</head>
<style>
h1 {
color: red;
}
* {
box-sizing: border-box;
}
.img-magnifier-container {
position: relative;
}
.img-magnifier-glass {
position: absolute;
border: 3px solid #000;
border-radius: 50%;
cursor: none;
/*Set the size of the magnifier glass:*/
width: 100px;
height: 100px;
}
</style>
<script>
function magnify(imgID, zoom) {
var img, glass, w, h, bw;
img = document.getElementById(imgID);
/*create magnifier glass:*/
glass = document.createElement("DIV");
glass.setAttribute("class", "img-magnifier-glass");
/*insert magnifier glass:*/
img.parentElement.insertBefore(glass, img);
/*set background properties for the magnifier glass:*/
glass.style.backgroundImage = "url('" + img.src + "')";
glass.style.backgroundRepeat = "no-repeat";
glass.style.backgroundSize = (img.width * zoom) + "px " + (img.height * zoom) + "px";
bw = 3;
w = glass.offsetWidth / 2;
h = glass.offsetHeight / 2;
/*execute a function when someone moves the magnifier glass over the image:*/
glass.addEventListener("mousemove", moveMagnifier);
img.addEventListener("mousemove", moveMagnifier);
/*and also for touch screens:*/
glass.addEventListener("touchmove", moveMagnifier);
img.addEventListener("touchmove", moveMagnifier);
function moveMagnifier(e) {
var pos, x, y;
/*prevent any other actions that may occur when moving over the image*/
e.preventDefault();
/*get the cursor's x and y positions:*/
pos = getCursorPos(e);
x = pos.x;
y = pos.y;
/*prevent the magnifier glass from being positioned outside the image:*/
if (x > img.width - (w / zoom)) {
x = img.width - (w / zoom);
}
if (x < w / zoom) {
x = w / zoom;
}
if (y > img.height - (h / zoom)) {
y = img.height - (h / zoom);
}
if (y < h / zoom) {
y = h / zoom;
}
/*set the position of the magnifier glass:*/
glass.style.left = (x - w) + "px";
glass.style.top = (y - h) + "px";
/*display what the magnifier glass "sees":*/
glass.style.backgroundPosition = "-" + ((x * zoom) - w + bw) + "px -" + ((y * zoom) - h + bw) + "px";
}
function getCursorPos(e) {
var a, x = 0, y = 0;
e = e || window.event;
/*get the x and y positions of the image:*/
a = img.getBoundingClientRect();
/*calculate the cursor's x and y coordinates, relative to the image:*/
x = e.pageX - a.left;
y = e.pageY - a.top;
/*consider any page scrolling:*/
x = x - window.pageXOffset;
y = y - window.pageYOffset;
return {x: x, y: y};
}
}
</script>
<body>
<div class="container">
<br>
<br>
<div class="text-center">
<h1>How To Create Image Magnifier Glass Using JavaScript</h1>
</div>
<br>
<div class="well">
<h1>Image Magnifier Glass</h1>
<div class="img-magnifier-container">
<img id="image" src="../image/demo4.jpg" width="600" height="400">
</div>
<script>
/* Initiate Magnify Function
with the id of the image, and the strength of the magnifier glass:*/
magnify("image", 3);
</script>
</div>
<div>
</body>
</html>