$_FILES is empty when I load images with javascript - javascript

I have a form to edit existing data but for some reason the images I load are not being detected in the var $_FILES.
The var $_FILES only detect data If I upload more images manually (without javascript code).
Here is my code to load images to the form.
// This images are loaded after the query is executed and then
// I take this images and insert in the form.
var images = document.getElementsByClassName("image-product");
var dataTransfer = new DataTransfer();
for (let image of images) {
fetch(image.src).then(res => res.blob()).then(blob => {
var file = new File([blob], image.id, blob);
dataTransfer.items.add(file);
listImagesForm.push(file);
});
}
var iptImg = document.getElementById("ipt-image");
iptImg.files = dataTransfer.files;
But if I go to the console and execute the command: document.getElementById("ipt-image").files I can see the information of all files.
EDIT:
The code that I use to submit form is simple:
<form class='form-validate' action='./database/db_product.php?action=update' method='POST' enctype='multipart/form-data'>;
<input type="file" multiple class="custom-file-input" id="ipt-image" name="ipt-image[]">
<button type="submit" class="btn btn-lg btn-primary">Save</button>
</form>
I remember again that if I upload more images after this they will be added to existing ones and the $_FILES will detect all the images.

Related

How to upload image via Javascript?

I am trying to upload an image to an input[type='file'] of another page.
Here is what I have so far:
const dT = new ClipboardEvent('').clipboardData || new DataTransfer();
dT.items.add(new File(result.products[pointer][3], 'product_image.png'));
document.querySelector('input[class="mkhogb32"]').files = dT.files;
console.log(dT);
console.log(document.querySelector('input[class="mkhogb32"]').files);
The code goes through and creates a file and adds it to the inputs files, however, the image never actually gets uploaded to the page:
Terminal of page
The image above shows the files of the input after my function ran, showing the function went through. However, on this particular page, when an image is uploaded the traditional way off picking a file off your desktop or drag and drop it changes the css, as it displays the image.
How can I get my injected file to trigger that same reaction?
The result.products[pointer][3] refers to an image src scraped from a previous page, how can I make the injected file contain this image?
In this example I'm picking a local image. The FileReader object will read the file as a data URL and when ready ('load') it will insert the data URL into the src attribute if the image.
var reader1 = new FileReader();
reader1.addEventListener('load', e => {
document.querySelector('#img').src = e.target.result;
});
document.addEventListener('DOMContentLoaded', e => {
document.forms.pickfile.file.addEventListener('change', e => {
reader1.readAsDataURL(e.target.files[0]);
});
});
<form name="pickfile">
<input name="file" type="file" />
</form>
<img id="img" />
I don't think that it is possible to add a file to an input[type="file"] element using JavaScript, but you can grab the formdata from a form and then add your own data to formdata.
In the example: When the user click on the submit I "copy" the formdata from the form (OK, there is no data in this example, but still...). I create a file object (maybe you already have a file object or a list of file objects) and set that as an object in formData. Lastly I post the formData as if it was a plain POST submit from the form.
Maybe this can help...
document.forms.pickfile.addEventListener('submit', e => {
e.preventDefault();
let svg = ['<?xml version="1.0"?><svg xmlns="http://www.w3.org/2000/svg" width="200" height="200"><rect fill="blue" width="200" height="200" x="0" y="0"/></svg>'];
let file = new File(svg, 'example.svg', {type: 'image/svg'});
let formData = new FormData(e.target);
formData.set('file', file, 'example.svg');
fetch('/', {
method: 'POST',
body: formData
})
.then(response => response.json())
.then(data => console.log(data));
});
<form name="pickfile">
<input name="file" type="file" />
<button>Send</button>
</form>

HTML Paste Clipboard File to File Input

I have a function that uploads a CSV file into a server via form submission.
It is working well, but I need to support copy and paste of CSV file from the actual file location to the input element.
I tried to do this code from a stackoverflow answer (https://stackoverflow.com/a/50427897/9751944)
const form = document.getElementById("new_document_attachment");
const fileInput = document.getElementById("document_attachment_doc");
fileInput.addEventListener('change', () => {
form.submit();
});
window.addEventListener('paste', e => {
fileInput.files = e.clipboardData.files;
});
<form id="new_document_attachment" method="post">
<div class="actions"><input type="submit" name="commit" value="Submit" /></div>
<input type="file" id="document_attachment_doc" />
</form>
It is working on images. But when I try it on CSV and other files, I am getting an error saying that the clipboard does not have any content
ie.
The first FileList and File are for the test image while the second one is for CSV

previous file is being disappear when clicking input type file

I am creating a web app in which I want to allow my users to select multiple files,
when my user select multiple files at a time it is working fine but when the user re-select again the previous files disappear,
here is my input field
<input type="file" id="uploadMultipleFiles" multiple />
I want my user to select multiple file and allow them to click multiple time without loosing the previous file selection
here is a JSFiddle for reference,
I can use javascript or jquery if necessary
Hope I explain this question properly
You can get that working using the JavaScript. You have to push the selected file in an array. when the user submit the form, you have to send the files to the server using ajax.
var input = document.getElementById('uploadMultipleFiles');
var btn = document.getElementById('btn');
var allFiles = [];
input.addEventListener('change', function(evnt){
for(var i=0; i<input.files.length; i++){
allFiles.push(input.files[i])
}
})
btn.addEventListener('click', function(evnt){
console.log('Loading Files')
allFiles.forEach( function(file){
console.log(file.name)
})
})
<input type="file" id="uploadMultipleFiles" multiple />
<br><br><br>
<button id="btn">
Console All Files
</button>

Ajax file upload: what happens by default in form.onsubmit()?

I have a Java servlet that receives a file, processes it and then writes the resulting file back through HttpServletResponse's OutputStream.
For upload, I use a simple form:
<form id="upload-form" action="MyServlet" method="POST" enctype="multipart/form-data">
Select file to convert:
<input type="file" id="file-select" name="myfile" />
<button type="submit" id="upload-button">Upload</button>
</form>
After the file has been processed, a download dialog opens automatically.
Since processing may take a while (something like 30 seconds plus upload time), I wanted to provide some progress information through a websocket on the same page. This works if I do this:
var uploadForm = document.getElementById("upload-form");
var fileSelect = document.getElementById("file-select");
var uploadButton = document.getElementById("upload-button");
var httpRequest = new XMLHttpRequest();
uploadForm.onsubmit = function(event) {
event.preventDefault();
event.stopPropagation();
var file = fileSelect.files[0];
var formData = new FormData();
formData.append("myfile", file, file.name);
httpRequest.open("POST", "MyServlet", true);
httpRequest.send(formData);
};
The essential commands here seem to be event.preventDefault and event.stopPropagation.
The thing is: with this code, I get my progress info - but my download window never appears. If I comment out the two commands, it's the other way around. What happens by default when submitting a form, and (how) can I trigger that manually, so that I get both progress info AND the resulting file?
Note: I'm not using jQuery so far.

How to show the image uploaded using HTML file control on a new page after form submission in PHP?

I've a form which contains following file upload control and image control:
<form action="rebate_preview.php" role="form" method="post" enctype="multipart/form-data">
<input type="hidden" name="hidden_path" id="hidden_path" value="">
<input type="file" name="rebate_image" id="rebate_image">
<img id="rebate_old_image" src="#" alt="your image" width="80" height="80"/>
<button type="submit" class="btn btn-primary">Submit</button>
</form>
Here I'm enabling the user to see the preview of the image he selected for upload without actually uploading the image to server using following jQuery code :
$(document).ready(function() {
function readURL(input) {
if (input.files && input.files[0]) {
var reader = new FileReader();
reader.onload = function (e) {
$('#rebate_old_image').attr('src', e.target.result);
$('#hidden_path').val(e.target.result)
}
reader.readAsDataURL(input.files[0]);
}
}
$("#rebate_image").change(function(){
readURL(this);
});
});
Now the problems I'm facing is I'm not able to show the same image preview on the next page i.e. on a file "rebate_preview.php" after form submission using image control. The next issue I'm facing is how should I store the values from array $_FILES on the page rebate_preview.php?
Remember still the image uploaded by user is not yet uploaded to the server.
The page rebate_preview.php is just a preview page with some other fields to preview the details.
How should I show this image on the page rebate_preview.php using image control and how should I store the $_FILES array data?
I had this problem a short while back when I was building an application, the best thing to create an OBJECT URL from the selected image when you select the file, you can then set your img src to that OBJECT URL data, which will render it to the page, for example lets say you have a file input with the id image_file. you could do this:
// Preview the image on the page
$('#image_file').change(function(e) {
var selected_file = $('#image_file').get(0).files[0];
selected_file = window.URL.createObjectURL(selected_file);
$('#preview_image').attr('src' , selected_file);
});
The source is now the BLOB representation of the image, you can then submit your form to upload the image or select another image to update the preview, hope this helps :)
Simple Solution?
in PHP script just do:
print "<img src='".$_POST['hidden_path']."'>";

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