javascript to zoom images

Question

I cant seem to get this to work. I'm trying to convert a javascript bookmarklet into a javascript onclick function to zoom in on images in the page.

The bookmarklet is as follows...

javascript:(function(){ function zoomImage(image, amt) { if(image.initialHeight == null) { /* avoid accumulating integer-rounding error */ image.initialHeight=image.height; image.initialWidth=image.width; image.scalingFactor=1; } image.scalingFactor*=amt; image.width=image.scalingFactor*image.initialWidth; image.height=image.scalingFactor*image.initialHeight; } var i,L=document.images.length; for (i=0;i<L;++i) zoomImage(document.images[i], 2); if (!L) alert("This page contains no images."); })();

But this is what I have so far but is not working properly...

The JS:

(function vbZoom() {
    function zoomImage(image, amt) {
        if (image.initialHeight == null) {
            image.initialHeight = image.height;
            image.initialWidth = image.width;
            image.scalingFactor = 1;
        }
        image.scalingFactor *= amt;
        image.width = image.scalingFactor * image.initialWidth;
        image.height = image.scalingFactor * image.initialHeight;
    }
    var i, L = document.images.length;
    for (i = 0; i < L; ++i) zoomImage(document.images[i], 2);
    if (!L) alert("This page contains no images.");
})();

The Link: (from an image)

<img id="vZoomIn" onclick="vbZoom()">

Please help, anyone.

EDIT: I should note... it partially works. What it currently does is makes images on the page twice as big upon loading but then the button does nothing at all.

Answer 1

var modal = document.getElementById('myModal');
var img = document.getElementById('myImg');
var modalImg = document.getElementById("img01");
var captionText = document.getElementById("caption");
img.onclick = function(){
    modal.style.display = "block";
    modalImg.src = this.src;
    modalImg.alt = this.alt;
 
}

modal.onclick = function() {
    img01.className += " out";
    setTimeout(function() {
       modal.style.display = "none";
       img01.className = "modal-content";
     }, 400);
    
 }

#myImg {
    border-radius: 5px;
    cursor: pointer;
    transition: 0.3s;
    display: block;
    margin-left: auto;
    margin-right: auto
}

#myImg:hover {opacity: 0.7;}

/* The Modal (background) */
.modal {
    display: none; /* Hidden by default */
    position: fixed; /* Stay in place */
    z-index: 1; /* Sit on top */
    padding-top: 100px; /* Location of the box */
    left: 0;
    top: 0;
    width: 100%; /* Full width */
    height: 100%; /* Full height */
    overflow: auto; /* Enable scroll if needed */
    background-color: rgb(0,0,0); /* Fallback color */
    background-color: rgba(0,0,0,0.9); /* Black w/ opacity */
}

/* Modal Content (image) */
.modal-content {
    margin: auto;
    display: block;
    width: 75%;
    //max-width: 75%;
}

/* Caption of Modal Image */
#caption {
    margin: auto;
    display: block;
    width: 80%;
    max-width: 700px;
    text-align: center;
    color: #ccc;
    padding: 10px 0;
    height: 150px;
}

/* Add Animation */
.modal-content, #caption {
    -webkit-animation-name: zoom;
    -webkit-animation-duration: 0.6s;
    animation-name: zoom;
    animation-duration: 0.6s;
}

.out {
  animation-name: zoom-out;
  animation-duration: 0.6s;
}

@-webkit-keyframes zoom {
    from {-webkit-transform:scale(1)}
    to {-webkit-transform:scale(2)}
}

@keyframes zoom {
    from {transform:scale(0.4)}
    to {transform:scale(1)}
}

@keyframes zoom-out {
    from {transform:scale(1)}
    to {transform:scale(0)}
}

/* The Close Button */
.close {
    position: absolute;
    top: 15px;
    right: 35px;
    color: #f1f1f1;
    font-size: 40px;
    font-weight: bold;
    transition: 0.3s;
}

.close:hover,
.close:focus {
    color: #bbb;
    text-decoration: none;
    cursor: pointer;
}


@media only screen and (max-width: 700px){
    .modal-content {
        width: 100%;
    }
}

<img id="myImg" src="https://s3-us-west-2.amazonaws.com/s.cdpn.io/3/journey_start_thumbnail.jpg" alt="Trolltunga, Norway" width="500" height="300">

<!-- The Modal -->
<div id="myModal" class="modal">
  <img class="modal-content" id="img01">
</div>

Answer 2

You can use fancybox

1. use Jquery then use fancybox css & js
2. use the fancy box html given below, it help to zoom your image as much you want.

<script src="https://cdn.jsdelivr.net/npm/jquery@3.5.1/dist/jquery.min.js"></script>

   <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/fancybox/3.5.7/jquery.fancybox.css">

   <a class="hidden-md hidden-lg" href="https://bdtender.com/tenderimage/Feb04/Feb04_BT040221-2A.jpg" data-fancybox="images" data-caption="My caption">
    <img src="https://bdtender.com/tenderimage/Feb04/Feb04_BT040221-2A.jpg" style="width:100%; height:auto;" alt="" />
   </a>

  <script src="https://cdnjs.cloudflare.com/ajax/libs/fancybox/3.5.7/jquery.fancybox.min.js"> 
 </script>

Answer 3

Wrapping the function in those brackets means it's called immediately and not available outside the brackets, known as Immediately-invoked function expression, change it to

function vbZoom() {
    function zoomImage(image, amt) {
        if (image.initialHeight == null) {
            image.initialHeight = image.height;
            image.initialWidth = image.width;
            image.scalingFactor = 1;
        }
        image.scalingFactor *= amt;
        image.width = image.scalingFactor * image.initialWidth;
        image.height = image.scalingFactor * image.initialHeight;
    }
    var i, L = document.images.length;
    for (i = 0; i < L; ++i) zoomImage(document.images[i], 2);
    if (!L) alert("This page contains no images.");
}

Actually there's a lot that should probably be changed in the code however that should at least work and be available to the rest of the page and not automatically called.