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Delete An Image() Object From Memory On Click Event Of Sibling Element — JavaScript

I have an image previewer that uses the JavaScript Image() object to preview images prior to them being processed with PHP. I have a div that contains an 'x' SVG graphic that is targeted with a click event to delete the image.
In the code below at the bottom of the function it uses evt.target and essentially removes the parent element that each image is inside to delete the image if the user wishes to do so.
This all works OK on a visual level, but even if the images are deleted (and they are removed from the HTML), when the 'submit' element on the form is clicked to upload the images, any deleted images are still processed. From what I can gather the images are stored in memory and are processed from there.
I've tried setting the image itself (the thumbnailElement in the JavaScript) to null and setting its src attribute to an empty string but this isn't working.
What is the best way to prevent these deleted image previews from being processed?
In the code below I've swapped out the SVG graphic for the 'x' to the letter 'x' to make it easier to read.
NOTE: I've showed the entire image uploader below - but it is the final part of the JS underneath // Delete Images that is part I need help with.
Codepen: https://codepen.io/emilychews/pen/WNjZVGZ
const dropZone = document.getElementById('drop-zone'),
showSelectedImages = document.getElementById('show-selected-images'),
fileUploader = document.getElementById('standard-upload-files')
dropZone.addEventListener("click", (evt) => {
// assigns the dropzone to the hidden input element so when you click 'select files' it brings up a file picker window
fileUploader.click();
});
// Prevent browser default when draging over
dropZone.addEventListener("dragover", (evt) => {
evt.preventDefault();
});
fileUploader.addEventListener("change", (evt) => {
// Clear the already selected images
showSelectedImages.innerHTML = "";
// this function is further down but declared here and shows a thumbnail of the image
[...fileUploader.files].forEach(updateThumbnail);
});
dropZone.addEventListener("drop", (evt) => {
evt.preventDefault();
// Clear the already selected images
showSelectedImages.innerHTML = "";
// assign dropped files to the hidden input element
if (evt.dataTransfer.files.length) {
fileUploader.files = evt.dataTransfer.files;
}
// function is declared here but written further down
[...evt.dataTransfer.files].forEach(updateThumbnail);
});
// updateThumbnail function that needs to be able to handle multiple files
function updateThumbnail(file) {
if (file.type.startsWith("image/")) {
const uploadImageWrapper = document.createElement('article'),
removeImage = document.createElement('div'),
thumbnailElement = new Image();
// 'x' that deletes the image
removeImage.classList.add("remove-image");
removeImage.innerHTML = 'x';
// image thumbnail
thumbnailElement.classList.add("drop-zone__thumb");
thumbnailElement.src = URL.createObjectURL(file);
// appending elements
showSelectedImages.append(uploadImageWrapper) // <article> element
uploadImageWrapper.append(removeImage) // 'x' to delete
uploadImageWrapper.append(thumbnailElement); // image thumbnail
// Delete images
removeImage.addEventListener('click', (evt) => {
if(evt.target) {
var deleteImage = removeImage.closest('article');
deleteImage.remove()
}
})
}
} // end of 'updateThumbnail' function
body {
margin: 0;
display: flex;
justify-content: center;
width: 100%;
}
form {
width: 30%;
}
#drop-zone {
border: 1px dashed;
width: 100%;
padding: 1rem;
margin-bottom: 1rem;
}
.select-files {
text-decoration: underline;
cursor: pointer;
}
/* image that is preview prior to form submit*/
.drop-zone__thumb {
width: 200px;
height: auto;
display: block;
}
#remove-x {
width: 1rem;
height: 1rem;
}
#submit-images {
margin: 1rem 0;
}
#show-selected-images {
display: flex;
}
<form id="upload-images-form" enctype="multipart/form-data" method="post">
<h1>Upload Your Images</h1>
<div id="drop-zone" class="drop-zone flex">
<p class="td text-center">DRAG AND DROP IMAGES HERE</p>
<p class="td text-center" style="margin: 0">Or</p>
<p class="tl text-center select-files text-bold pointer">Select Files</p>
</div>
<input id="standard-upload-files" style="display:none" style="min-width: 100%" type="file" name="standard-upload-files[]" multiple>
<input type="submit" name="submit-images" id="submit-images" value="SUBMIT IMAGES">
<div id="show-selected-images"></div>
</form>

Problem:
You are not updating fileUploader.files when you add/remove an item.
Solution
Every time you drop/remove a file you need to update the fileUploader input. The first step is to create a function to handle the FileList object and change only two lines of your code:
//--> to create a FileList
function getFileListItems (files) {
var transferObject = new ClipboardEvent("").clipboardData || new DataTransfer()
for (var i = 0; i<files.length; i++) transferObject.items.add(files[i])
return transferObject.files;
}
Add files during the drop event:
//--> Updating files during drop event
fileUploader.files = getFileListItems([...fileUploader.files, ...evt.dataTransfer.files]);
Removing a file:
fileUploader.files = getFileListItems([...fileUploader.files].filter(f => file!==f));
See a complete working example:
const dropZone = document.getElementById("drop-zone"),
showSelectedImages = document.getElementById("show-selected-images"),
fileUploader = document.getElementById("standard-upload-files");
dropZone.addEventListener("click", (evt) => {
// assigns the dropzone to the hidden input element so when you click 'select files' it brings up a file picker window
fileUploader.click();
});
// Prevent browser default when draging over
dropZone.addEventListener("dragover", (evt) => {
evt.preventDefault();
});
fileUploader.addEventListener("change", (evt) => {
// this function is further down but declared here and shows a thumbnail of the image
[...fileUploader.files].forEach(updateThumbnail);
});
function getFileListItems(files) {
var transferObject = new ClipboardEvent("").clipboardData || new DataTransfer()
for (var i = 0; i < files.length; i++) transferObject.items.add(files[i])
return transferObject.files;
}
dropZone.addEventListener("drop", (evt) => {
evt.preventDefault();
// assign dropped files to the hidden input element
if (evt.dataTransfer.files.length) {
fileUploader.files = getFileListItems([...fileUploader.files, ...evt.dataTransfer.files]);
}
// function is declared here but written further down
[...evt.dataTransfer.files].forEach(updateThumbnail);
});
// updateThumbnail function that needs to be able to handle multiple files
function updateThumbnail(file) {
if (file.type.startsWith("image/")) {
let uploadImageWrapper = document.createElement("article"),
removeImage = document.createElement("div"),
thumbnailElement = new Image();
// 'x' that deletes the image
removeImage.classList.add("remove-image");
removeImage.innerHTML =
'<svg id="remove-x" viewBox="0 0 150 150"><path fill="#000" d="M147.23,133.89a9.43,9.43,0,1,1-13.33,13.34L75,88.34,16.1,147.23A9.43,9.43,0,1,1,2.76,133.89L61.66,75,2.76,16.09A9.43,9.43,0,0,1,16.1,2.77L75,61.66,133.9,2.77a9.42,9.42,0,1,1,13.33,13.32L88.33,75Z"/></svg>';
// image thumbnail
thumbnailElement.classList.add("drop-zone__thumb");
thumbnailElement.src = URL.createObjectURL(file);
// appending elements
showSelectedImages.append(uploadImageWrapper); // <article> element
uploadImageWrapper.append(removeImage); // 'x' to delete
uploadImageWrapper.append(thumbnailElement); // image thumbnail
// Delete images
removeImage.addEventListener("click", (evt) => {
if (evt.target) {
var deleteImage = removeImage.parentElement;
deleteImage.remove();
fileUploader.files = getFileListItems([...fileUploader.files].filter(f => file !== f));
}
});
}
} // end of 'updateThumbnail' function
body {
margin: 0;
display: flex;
justify-content: center;
width: 100%;
}
form {
width: 30%;
}
#drop-zone {
border: 1px dashed;
width: 100%;
padding: 1rem;
margin-bottom: 1rem;
}
.select-files {
text-decoration: underline;
cursor: pointer;
}
/* image that is preview prior to form submit*/
.drop-zone__thumb {
width: 200px;
height: auto;
display: block;
}
#remove-x {
width: 1rem;
height: 1rem;
}
#submit-images {
margin: 1rem 0;
}
#show-selected-images {
display: flex;
}
<form id="upload-images-form" enctype="multipart/form-data" method="post">
<h1>Upload Your Images</h1>
<div id="drop-zone" class="drop-zone flex">
<p class="td text-center">DRAG AND DROP IMAGES HERE</p>
<p class="td text-center" style="margin: 0">Or</p>
<p class="tl text-center select-files text-bold pointer">Select Files</p>
</div>
<input id="standard-upload-files" style="display:none" style="min-width: 100%" type="file" name="standard-upload-files[]" multiple>
<input type="submit" name="submit-images" id="submit-images" value="SUBMIT IMAGES">
<div id="show-selected-images"></div>
</form>
Working example

This is because when a form submitted, it doesn't submit every HTML element in the form, but only values of input, textarea, pressed button and some others that have name attribute.
So what you need is clear the file input field too:
const showSelectedImages = document.getElementById("preview");
const input = document.getElementById("test");
function updateThumbnail(file) {
if (file.type.startsWith("image/")) {
// image and 'x' to delete wrapper
const uploadImageWrapper = document.createElement('article')
// div that holds the 'x' to delete
const removeImage = document.createElement('div')
// image preview element
thumbnailElement = new Image()
// 'x' that deletes the image
removeImage.classList.add("remove-image")
removeImage.innerHTML = 'x'
// image thumbnail
thumbnailElement.classList.add("drop-zone__thumb")
thumbnailElement.src = URL.createObjectURL(file)
// appending elements
showSelectedImages.append(uploadImageWrapper) // <article> element
uploadImageWrapper.append(removeImage) // 'x' to delete
uploadImageWrapper.append(thumbnailElement) // image thumbnail
// Delete Images when the 'x' div is clicked
removeImage.addEventListener('click', (evt) => {
if (evt.target) {
var deleteImage = removeImage.parentElement
deleteImage.remove();
/* for single file input is enough clear value property */
// input.value = null;
/* for multiple files input we'll need recreate new files list excluding deleted file */
const dt = new DataTransfer();
for (let f of input.files) {
if (f !== file)
dt.items.add(f);
}
input.files = dt.files;
}
})
}
}
function updateThumbnails(files) {
showSelectedImages.innerHTML = ""; //remove all previous previews
for (let f of files)
updateThumbnail(f);
}
function showform(form) {
const list = {};
for (let i of [...new FormData(form).entries()]) {
const key = i[0].match(/^([^\[]+)\[\]$/);
if (key) {
if (!list[key[1]])
list[key[1]] = [];
list[key[1]][list[key[1]].length] = i[1];
} else
list[i[0]] = i[1];
}
console.log(list)
return false;
}
.remove-image {
cursor: pointer;
}
article {
display: inline-block;
}
<form type="post" onsubmit="return showform(this);">
<input type="hidden" name="myHiddenInput" value="blah">
<input type="file" name="test[]" id="test" oninput="updateThumbnails(this.files)" multiple>
<span id="preview"></span>
<button type="submit">submit</button>
</form>

How to separete div blocks with the same class but diffent features

Good day!
I have a pop-up section. There are 2 div blocks in it with identical structure. The idea is to have 2 buttons (one is to edit a profile the other is to create a new card with some info) that will call this pop-up, but i need to track which one is called. The popup itself has a darker background compare to main page and a form. I have thought of a modifier popup__container_type_(edit/create) that has a display: none command so when i toggle it it the popup would appear with the right form. Most likely my logic was mistaken. I dont know how to distiguish them (div blocks) correctly.
Another problem is that closebutton seems to work for one form only.
Any help would be great!
HTML:
<section class="popup">
<div class="popup__container popup__container_type_edit">
<button type="button" class="popup__cancelbutton"></button>
<form class="popup-form" name="form">
<h2 class="popup-form__title">Header 1</h2>
<input type="text" class="popup-form__input popup-form__input_type_name" name="name">
<input type="text" class="popup-form__input popup-form__input_type_job" name="job">
<button type="submit" class="popup-form__savebutton">Save</button>
</form>
</div>
<div class="popup__container popup__container_type_create">
<button type="button" class="popup__cancelbutton"></button>
<form class="popup-form" name="form">
<h2 class="popup-form__title">Header 2</h2>
<input type="text" class="popup-form__input popup-form__input_type_place" placeholder="Name of the place" name="place">
<input type="text" class="popup-form__input popup-form__input_type_imagelink" placeholder="Image link" name="imagelink">
<button type="submit" class="popup-form__savebutton">Create</button>
</form>
</div>
</section>
JS:
let popUpSection = document.querySelector(`.popup`);
let cancelButton = popUpSection.querySelector(`.popup__cancelbutton`);
let popUpContainer = popUpSection.querySelector(`.popup__container`);
let formElement = popUpSection.querySelector(`.popup-form`);
let newInputName = popUpSection.querySelector(`.popup-form__input_type_name`);
let newInputJob = popUpSection.querySelector(`.popup-form__input_type_job`);
let inputName = document.querySelector(`.profile-info__title`);
let inputJob = document.querySelector(`.profile-info__text`);
let editButton = document.querySelector(`.profile-info__editbutton`);
let createButton = document.querySelector(`.profile__addbutton`);
//Open / close popup section
let formTogglePopUp = () => {
if (!popUpSection.classList.contains(`popup_acitve`)){
//Autofill
newInputName.value = inputName.textContent;
newInputJob.value = inputJob.textContent;
}
popUpSection.classList.toggle(`popup_active`);
}
//Save input changes
function popUpFormSaved (event) {
event.preventDefault();
inputName.textContent = newInputName.value;
inputJob.textContent = newInputJob.value;
formTogglePopUp();
}
formElement.addEventListener('submit', popUpFormSaved);
cancelButton.addEventListener('click', formTogglePopUp);
editButton.addEventListener('click', formTogglePopUp);
createButton.addEventListener(`click`, formTogglePopUp);
CSS:
.popup__container
{
display: block; *by default*
}
.popup__container_type_(edit/create)
{
display: none;
}
.popup
{
display:none;
}
.popup__active
{
display: flex;
}

You can do it with js, set ids and use them instead of class, it's more easy.
function popUpEdit() {
document.getElementById("popUp").style.display = "block";
document.getElementById("popUpEdit").style.display = "block";
}
function popUpCreate() {
document.getElementById("popUp").style.display = "block";
document.getElementById("popUpCreate").style.display = "block";
}
#popUp, #popUpEdit, #popUpCreate {
display: none;
}
<div class="smt">
Hello
<button onclick="popUpEdit()">Edit</button>
</div>
<div class="smt">Hello
<button onclick="popUpCreate()">Create</button>
</div>
<section id="popUp">
<div>popUp</div>
<div id="popUpEdit">Edit-popup</div>
<div id="popUpCreate">Create-popup</div>
</section>

Generaly, I do that this way:
const SectionPopUp = document.querySelector('section.popup')
function show(elm)
{
SectionPopUp.classList.toggle('Create','Create'===elm)
SectionPopUp.classList.toggle('Edit','Edit'===elm)
}
section.popup,
section.popup.Edit > div:not(.popup__container_type_edit),
section.popup.Create > div:not(.popup__container_type_create) {
display:none;
}
section.popup.Edit,
section.popup.Create {
display:block;
}
/* cosmetic part, just for testing here */
section.popup > div {
border : 1px solid aqua;
padding : .6em;
margin : 1em;
width : 15em;
}
div.popup__container_type_create {
border-color: orange !important;
}
<button onclick="show('Edit')"> show Edit </button>
<button onclick="show('Create')"> show Create </button>
<button onclick="show('')"> show none </button>
<section class="popup">
<div class="popup__container popup__container_type_edit">
pop-up edit content
</div>
<div class="popup__container popup__container_type_create">
pop-up create content
</div>
</section>

jquery preview image not working

So I'm trying to implement a preview button so that when my users clicks on the upload button image they could have a preview but the thing is that it is not working, I wonder why ?? A brief description : I have a js function that creates new elements and append it to a p tag date. It is in this function that is going to create the preview image code
// code for creating new elements
function createElements(){
const userQuestions = document.querySelector('#userQuestions');
userQuestions.insertAdjacentHTML(
'beforeend', '<div class="uploader" onclick="$(\'#filePhoto\').click()"><p id="bg-text">No image</p></div><input type="file" name="userprofile_picture" id="filePhoto" style="display:block;width:185px;" /></center><div class="grid-container">'
);
}
///Code to preview image
function handleImage(e) {
var imageLoader = document.getElementById('filePhoto');
imageLoader.addEventListener('change', handleImage, false);
var reader = new FileReader();
reader.onload = function (event) {
$('.uploader').html( '<img width="300px" height="350px" src="'+event.target.result+'"/>' );
}
reader.readAsDataURL(e.target.files[0]);
}
.uploader {width:50%;height:35%;background:#f3f3f3;border:2px dashed #0091ea;}
<html>
<head>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
</head>
<body>
<div id="userQuestions"></div>
<button type="button" onclick="createElements()">add elements</button>
</body>
</html>
If you run the snippet above you can see that the button is woeking but the preview is not showing. Could someone help me?

HTML:
<div class="row">
<div class="col-xs-4">
<div class="form-group">
<label>Company Logo</label>
<input type="file" class="form-control" value="" name="companyLogo" id="companyLogo" accept="image/*" />
</div>
</div>
<div id="displayImage">
<img id="imgData" src="#" alt="your image" height="150px" width="150px" />
</div>
</div>
JavaScript:
$("#companyLogo").change(function(e) {
if(e.target.value === "") {
$("#displayImage").hide();
} else {
$("#displayImage").show();
}
readURL(this);
});
function readURL(input) {
if (input.files && input.files[0]) {
var reader = new FileReader();
reader.onload = function(e) {
$("#imgData").attr("src", e.target.result);
}
reader.readAsDataURL(input.files[0]);
}
}

Short n simple
No need to create an element on click.
Just add an image tag and set a default image like no image selected or something like that.
The following code will help you
<input type="file" name="myCutomfile" id="myCutomfile"/>
<img id="customTargetImg" src="default.jpg" width="400" height="250">
$("#myCutomfile").change(function() {
if (this.files && this.files[0]) {
var reader = new FileReader();
reader.onload = function (e) {
$('#customTargetImg').attr('src', e.target.result);
}
reader.readAsDataURL(this.files[0]);
}
});

Take advantage of jQuery -- particularly using
event handlers
delegated event handlers for dynamically-created elements
tree traversal methods.
$(function() {
var userQuestions = $('#userQuestions');
// create onclick event handler for your button
$('#addElements').click(function() {
// IDs must be unique - since you can have an arbitrary number of filePhoto, use a class instead
userQuestions.append(
'<div class="uploader"><p id="bg-text">No image</p></div><input type="file" name="userprofile_picture" class="filePhoto" /><div class="grid-container"></div>'
);
});
// create delegated onclick event handler for your .uploader
userQuestions.on('click', '.uploader', function() {
// you only want to target the file input immediately after it
$(this).next('[type=file]').click();
});
// create delegated onchange event handler for your .filePhoto
userQuestions.on('change', '.filePhoto', function() {
// find related uploader
var uploader = $(this).prev('.uploader');
// check file was given
if (this.files && this.files.length) {
var reader = new FileReader();
reader.onload = function(event) {
uploader.html('<img width="300px" height="350px" src="' + event.target.result + '"/>');
}
reader.readAsDataURL(this.files[0]);
}
});
});
.uploader {
width: 50%;
height: 35%;
background: #f3f3f3;
border: 2px dashed #0091ea;
}
.filePhoto {
display: block;
width: 185px;
}
<html>
<head>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
</head>
<body>
<div id="userQuestions"></div>
<!-- added ID attribute -->
<button type="button" id="addElements">add elements</button>
</body>
</html>
Edit
This answer is a non-jQuery solution based off your comment.
// code for creating new elements
function createElements() {
// no need to document.querySelector if the selector is an ID
const userQuestions = document.getElementById('userQuestions');
// you want to use onclick/onchange attributes here as they are dynamically created
userQuestions.insertAdjacentHTML(
'beforeend', '<div class="uploader" onclick="selectFile(this)"><p id="bg-text">No image</p></div><input type="file" name="userprofile_picture" onchange="handleImage(this)" />'
);
}
// trigger click on file input that follows the uploader
function selectFile(uploader) {
uploader.nextSibling.click();
}
///Code to preview image
function handleImage(input) {
if (input.files.length) {
var reader = new FileReader();
reader.onload = function(e) {
input.previousSibling.innerHTML =
'<img width="300px" height="350px" src="' + e.target.result + '"/>';
}
reader.readAsDataURL(input.files[0]);
}
}
.uploader {
width: 50%;
height: 35%;
background: #f3f3f3;
border: 2px dashed #0091ea;
}
.filePhoto {
display: block;
width: 185px;
}
<html>
<head>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
</head>
<body>
<div id="userQuestions"></div>
<button type="button" onclick="createElements()">add elements</button>
</body>
</html>

upload with multiple image preview

I am using this source: http://opoloo.github.io/jquery_upload_preview/
until now, I can upload one image with preview.
<style type="text/css">
.image-preview {
width: 200px;
height: 200px;
position: relative;
overflow: hidden;
background-color: #000000;
color: #ecf0f1;
}
input[type="file"] {
line-height: 200px;
font-size: 200px;
position: absolute;
opacity: 0;
z-index: 10;
}
label {
position: absolute;
z-index: 5;
opacity: 0.7;
cursor: pointer;
background-color: #bdc3c7;
width: 200px;
height: 50px;
font-size: 20px;
line-height: 50px;
text-transform: uppercase;
top: 0;
left: 0;
right: 0;
bottom: 0;
margin: auto;
text-align: center;
}
</style>
<script type="text/javascript">
$(document).ready(function() {
$("image-preview").each(
function(){
$.uploadPreview({
input_field: $(this).find(".image-upload"),
preview_box: this,
label_field: $(this).find(".image-label")
});
}
);
});
</script>
<!--| catatan penting: yang penting action="" & input type="file" name="image" |-->
<form action="upload.php" method="POST" enctype="multipart/form-data">
<div class="image-preview">
<label for="image-upload" class="image-label">+ GAMBAR</label>
<input type="file" name="my_field[]" class="image-upload" />
</div>
<div class="image-preview">
<label for="image-upload" class="image-label">+ GAMBAR</label>
<input type="file" name="my_field[]" class="image-upload" />
</div>
<input type="submit"/>
</form>
then try to add more div class image preview, i want add another button with image preview. i don't want multiple upload with one button.
$(document).ready(function() {$.uploadPreview => use id, of course when change to class and add more div, when upload a button, another button will change. i am confused with the logic. Anyone can help? maybe using array but, i don't know how..

Since upload button is dependent on state of uploadPreview you need to initialize for each div separately to get separate upload buttons.
Change your html like this give each container a class say imgBox
<div class="imgBox">
<label for="image-upload" class="image-label">Choose File</label>
<input type="file" name="image" class="image-upload" />
</div>
.....
....
...
<div class="imgBox">
<label for="image-upload" class="image-label">Choose File</label>
<input type="file" name="image" class="image-upload" />
</div>
..
Now initialize each one using jquery each()
$(".imgBox").each(
function(){
$.uploadPreview({
input_field: $(this).find(".image-upload"),
preview_box: this,
label_field: $(this).find(".image-label")
});
});

I created a simple image uploading index.html file for image uploading and preview.
Needs j-query.No need of extra plugins.
If you have any questions ask me ;)
//to preview image you need only these lines of code
var imageId=idOfClicked;
var output = document.getElementById(imageId);
output.src = URL.createObjectURL(event.target.files[0]);
Check it here:
https://jsfiddle.net/chs3s0jk/6/

I have one better option for the file upload it's easy to use and you can try it.
window.onload = function(){
if(window.File && window.FileList && window.FileReader){
$(document).on("change",'.file', function(event) {
var files = event.target.files; //FileList object
var output = document.getElementById("upload-preview");
$("#upload-preview").html("");
if(files.length>5){
$(".file").after("<div class='alert alert-error'><span class='close'></span>Maximum 5 files can be uploaded.</div>");
$(this).val("");
return false;
}
else{
$(".file").next(".alert").remove();
}
for(var i = 0; i< files.length; i++)
{
var file = files[i];
//Only pics
// if(!file.type.match('image'))
if(file.type.match('image.*')){
if(this.files[0].size < 2097152){
// continue;
var picReader = new FileReader();
picReader.addEventListener("load",function(event){
var picFile = event.target;
var div = document.createElement("div");
div.className = "upload-preview-thumb";
div.style.backgroundImage = 'url('+picFile.result+')';
output.insertBefore(div,null);
});
//Read the image
$('#clear, #upload-preview').show();
picReader.readAsDataURL(file);
}else{
alert("Image Size is too big. Minimum size is 1MB.");
$(this).val("");
}
}else{
alert("You can only upload image file.");
$(this).val("");
}
}
});
$(".file2").change(function(event){
var err=0;
var input = $(event.currentTarget);
var ele = $(this);
var file = input[0].files[0];
var u = URL.createObjectURL(this.files[0]);
var w = ele.attr("data-width");
var h = ele.attr("data-height");
var img = new Image;
img.onload = function(){
if(w){
if(img.width!=w || img.height!=h){
ele.parent().find(".alert").remove();
ele.parent().find(".upload-preview").before("<div class='alert alert-error'>Please upload a image with specified dimensions.</div>");
ele.val("");
}
else{
ele.parent().find(".alert").remove();
}
}
};
img.src = u;
var nh;
if($(this).attr('data-preview')=='full')
nh = (h/w*150)
else
nh=150
var preview = ele.parent().find(".upload-preview");
var reader = new FileReader();
preview.show();
reader.onload = function(e){
image_base64 = e.target.result;
preview.html("<div class='upload-preview-thumb' style='height:"+nh+"px;background-image:url("+image_base64+")'/><div>");
};
reader.readAsDataURL(file);
});
}
else
{
console.log("Your browser does not support File API");
}
}
above code save as one js file like file-upload.js
then link it to your file where you want perview.
i.e.
<script src="js/file-upload.js" type="text/javascript"></script>
use this kind of example for the input type
<input type="file" class="file2" name="page-image" id="page-image"/>
that works on the class that name is "file2" that class you given to the input field that able to create preview.
full structure something like below.
HTML Code you can try
<input type="file" class="file2" name="page-image[]" id="page-image"/>
<div class="clearfix"></div>
<div class="upload-preview" style="display: block;">
<div class="upload-preview-thumb">
// perview genereate here
// you can display image also here if uploaded throw the php condition in edit image part
</div>
</div>
<input type="file" class="file2" name="page-image[]" id="page-image"/>
<div class="clearfix"></div>
<div class="upload-preview" style="display: block;">
<div class="upload-preview-thumb">
// perview genereate here
// you can display image also here if uploaded throw the php condition in edit image part
</div>
</div>
CSS
.upload-preview {
border: 1px dashed #ccc;
display: block;
float: left;
margin-top: 10px;
padding: 5px;
}
.upload-preview-thumb {
background-position: 50% 25%;
background-size: cover;
float: left;
margin: 5px;
position: relative;
width: 139px;
}
Hope this works and in future it's helpful for you.
Thanks.

How to make html div with text over image downloadable/savable for users?

I have a div that takes a user image and places user text over it. My goal is for the users to, after seeing the preview and customizing the image/text to their like, be able to download or save the image with the click of a button. Is this possible? Here's my code: (I'm new to html/css so please forgive ugly formatting/methods)
HTML:
<script `src="https://cdnjs.cloudflare.com/ajax/libs/html2canvas/0.4.1/html2canvas.min.js"></script>`
<p>DOM-rendered</p>
<p> </p>
<div id="imagewrap" class="wrap" style="border-style: solid;">
<img src="../images/environment.gif" id="img_prev" width="640" height="640" />
<h3 class="desc">Something Inspirational</h3>
</div>
<div id="canvasWrapper" class="outer">
<p>Canvas-rendered (try right-click, save image as!)</p>
<p>Or, <a id="downloadLink" download="cat.png">Click Here to Download!</a>
</div>
CSS:
.desc {
text-align: center;
}
.outer, .wrap, .html2canvas, .image_text {
display: inline-block;
vertical-align: top;
}
.wrap {
text-align: center;
}
#imagewrap {
background-color: white;
}
JavaScript:
window.onload = function() {
html2canvas(document.getElementById("imagewrap"), {
onrendered: function(canvas) {
canvas.className = "html2canvas";
document.getElementById("canvasWrapper").appendChild(canvas);
var image = canvas.toDataURL("image/png");
document.getElementById("downloadLink").href = image;
},
useCORS: true
});
}
function changePicture(image) {
var at = $(image).attr('at');
var newpath = '../images/' + at;
$("#img_prev").attr('src', newpath);
}
function readURL(input) {
if (input.files && input.files[0]) {
var reader = new FileReader();
reader.onload = function (e) {
$('#img_prev')
.attr('src', e.target.result)
.width(640)
.height(640);
};
reader.readAsDataURL(input.files[0]);
}
};
$(document).on("click", '.font-names li a', function() {
$("#imagewrap h3").css("font-family", $(this).parent().css("font-family"));
$("#new_tile_font_style").val($(this).parent().css("font-family"));
});
$(document).on("click", '.font-sizes li a', function() {
$("#imagewrap h3").css("font-size", $(this).parent().css("font-size"));
$("#new_tile_font_size").val($(this).parent().css("font-size") + "px");
});
$(document).on("click", '.font-colors li a', function() {
$("#imagewrap h3").css("color", $(this).parent().css("color"));
$("#new_tile_font_color").val($(this).parent().css("color"));
});
$("#new_tile_quote").on('keyup', function() {
var enteredText = $("#new_tile_quote").val().replace(/\n/g, "<br>");
$("#imagewrap h3").html(enteredText);
});

What you're trying to accomplish is entirely possible using just HTML, JS, and CSS, with no server-side code. Here is a simplified demo that uses the html2canvas library to render your entire DOM element to a canvas, where the user can then download it.
Be sure to click "Full page" on the demo so you can see the whole thing!
window.onload = function() {
html2canvas(document.getElementById("imagewrap"), {
onrendered: function(canvas) {
canvas.className = "html2canvas";
document.getElementById("canvasWrapper").appendChild(canvas);
var image = canvas.toDataURL("image/png");
document.getElementById("downloadLink").href = image;
},
useCORS: true
});
}
.desc {
text-align: center;
}
.outer, .wrap, .html2canvas, .image_text {
display: inline-block;
vertical-align: top;
}
.wrap {
text-align: center;
}
#imagewrap {
background-color: white;
}
#wow {
color: red;
display: block;
transform: translate(0px, -12px) rotate(-10deg);
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/html2canvas/0.4.1/html2canvas.min.js"></script>
<div class="outer">
<p>DOM-rendered</p>
<p> </p>
<div id="imagewrap" class="wrap" style="border-style: solid;">
<img src="https://i.imgur.com/EFM76Qe.jpg?1" id="img_prev" width="170" />
<h3 class="desc">Something <br /><span style="color: blue;">Inspirational</span></h3>
<span id="wow">WOW!</span>
</div>
</div>
<div id="canvasWrapper" class="outer">
<p>Canvas-rendered (try right-click, save image as!)</p>
<p>Or, <a id="downloadLink" download="cat.png">Click Here to Download!</a>
</div>

Here's a quick demo that shows how to use JavaScript to convert your markup into a canvas, then render that into an image and replace it on the page.
document.getElementById('generate').onclick = generateImage;
function generateImage() {
var container = document.getElementById('image_text');
var imgPrev = document.getElementById('img_prev');
var desc = document.getElementById('desc');
var canvas = document.createElement('canvas');
var context = canvas.getContext('2d');
canvas.setAttribute('width', container.clientWidth);
canvas.setAttribute('height', container.clientHeight);
context.drawImage(imgPrev, 0, 0);
context.font = "bold 20px serif";
context.fillText(desc.innerHTML, 0, container.clientHeight-20);
context.strokeRect(0, 0, canvas.width, canvas.height);
var dataURL = canvas.toDataURL();
var imgFinal = new Image();
imgFinal.src = dataURL;
container.parentNode.insertBefore(imgFinal, container.nextSibling);
container.remove();
document.getElementById('generate').remove();
}
#image_text {
display: inline-block;
border: 1px solid #000;
}
<div id="image_text">
<div class="wrap">
<img src= "https://placekitten.com/g/200/300" id="img_prev" crossorigin="anonymous" />
<h3 id="desc" contenteditable>Something Inspirational</h3>
</div>
</div>
<button id="generate">Generate Image</button>
You can replace the image file with anything you like. I've added a crossorigin property to the img tag, and this is because canvases that use resources from other sites cannot be exported unless a crossorigin attribute is specified (if your scripts and images are on the same domain, this is unnecessary).
I've also made the h3 tag editable. You can click on the text and start typing to change what it says, then click "generate image" and save the rendered output.
This script is just a demonstration. It is not bulletproof, it is only a proof-of-concept that should help you understand the techniques being used and apply those techniques yourself.
The javascript creates a canvas element (detached from the DOM), and sizes it according to the container div in your markup. Then it inserts the image into the canvas (it inserts it at the top-left corner), loads the text from your h3 tag and puts it near the bottom-left of the canvas, and converts that canvas to a data-uri. Then it creates a new img element after the container and deletes the container and button.