I would like to upload a file asynchronously with jQuery. This is my HTML:
<span>File</span>
<input type="file" id="file" name="file" size="10"/>
<input id="uploadbutton" type="button" value="Upload"/>
And here my Jquery code:
$(document).ready(function () {
$("#uploadbutton").click(function () {
var filename = $("#file").val();
$.ajax({
type: "POST",
url: "addFile.do",
enctype: 'multipart/form-data',
data: {
file: filename
},
success: function () {
alert("Data Uploaded: ");
}
});
});
});
Instead of the file being uploaded, I am only getting the filename. What can I do to fix this problem?
I am using the jQuery Form Plugin to upload files.
转载于:https://stackoverflow.com/questions/166221/how-can-i-upload-files-asynchronously
Note: This answer is outdated, it is now possible to upload files using XHR.
You cannot upload files using XMLHttpRequest (Ajax). You can simulate the effect using an iframe or Flash. The excellent jQuery Form Plugin that posts your files through an iframe to get the effect.
An important thing to understand with the "new" HTML5 file API is that is wasn't supported until IE 10. If the specific market you're aiming at has a higher-than-average prepensity toward older versions of Windows, you might not have access to it.
Going into 2017, about 5% of browsers are one of IE 6, 7, 8 or 9. If you head into a big corporation (eg this is a B2B tool, or something you're delivering for training) that number can rocket. Just a few months ago —in 2016— I dealt with a company using IE8 on over 60% of their machines.
So before you do anything: check what browser your users use. If you don't, you'll learn a quick and painful lesson in why "works for me" isn't good enough in a deliverable to a client.
My answer from 2008 follows.
However, there are viable non-JS methods of file uploads. You can create an iframe on the page (that you hide with CSS) and then target your form to post to that iframe. The main page doesn't need to move.
It's a "real" post so it's not wholly interactive. If you need status you need something server-side to process that. This varies massively depending on your server. ASP.NET has nicer mechanisms. PHP plain fails, but you can use Perl or Apache modifications to get around it.
If you need multiple file-uploads, it's best to do each file one at a time (to overcome maximum file upload limits). Post the first form to the iframe, monitor its progress using the above and when it has finished, post the second form to the iframe, and so on.
Or use a Java/Flash solution. They're a lot more flexible in what they can do with their posts...
There are various ready-made plugins on doing file upload for jQuery.
Doing this kind of uploading hacks is not an enjoyable experience, so people enjoy using ready-made solutions.
Here's few:
You can search for more projects on NPM (using "jquery-plugin" as the keyword) or on Github.
A solution I found was to have the <form> target a hidden iFrame. The iFrame can then run JS to display to the user that it's complete (on page load).
I recommend using the Fine Uploader plugin for this purpose. Your JavaScript code would be:
$(document).ready(function() {
$("#uploadbutton").jsupload({
action: "addFile.do",
onComplete: function(response){
alert( "server response: " + response);
}
});
});
I've written this up in a Rails environment. It's only about five lines of JavaScript, if you use the lightweight jQuery-form plugin.
The challenge is in getting AJAX upload working as the standard remote_form_for doesn't understand multi-part form submission. It's not going to send the file data Rails seeks back with the AJAX request.
That's where the jQuery-form plugin comes into play.
Here’s the Rails code for it:
<% remote_form_for(:image_form,
:url => { :controller => "blogs", :action => :create_asset },
:html => { :method => :post,
:id => 'uploadForm', :multipart => true })
do |f| %>
Upload a file: <%= f.file_field :uploaded_data %>
<% end %>
Here’s the associated JavaScript:
$('#uploadForm input').change(function(){
$(this).parent().ajaxSubmit({
beforeSubmit: function(a,f,o) {
o.dataType = 'json';
},
complete: function(XMLHttpRequest, textStatus) {
// XMLHttpRequest.responseText will contain the URL of the uploaded image.
// Put it in an image element you create, or do with it what you will.
// For example, if you have an image elemtn with id "my_image", then
// $('#my_image').attr('src', XMLHttpRequest.responseText);
// Will set that image tag to display the uploaded image.
},
});
});
And here’s the Rails controller action, pretty vanilla:
@image = Image.new(params[:image_form])
@image.save
render :text => @image.public_filename
I’ve been using this for the past few weeks with Bloggity, and it’s worked like a champ.
I've come across a few really powerful jQuery-based file upload libraries. Check these out:
This AJAX file upload jQuery plugin uploads the file somehwere, and passes the response to a callback, nothing else.
<input type="file">-- Use as little as --
$('#one-specific-file').ajaxfileupload({
'action': '/upload.php'
});
-- or as much as --
$('input[type="file"]').ajaxfileupload({
'action': '/upload.php',
'params': {
'extra': 'info'
},
'onComplete': function(response) {
console.log('custom handler for file:');
alert(JSON.stringify(response));
},
'onStart': function() {
if(weWantedTo) return false; // cancels upload
},
'onCancel': function() {
console.log('no file selected');
}
});
With HTML5 you can make file uploads with Ajax and jQuery. Not only that, you can do file validations (name, size, and MIME type) or handle the progress event with the HTML5 progress tag (or a div). Recently I had to make a file uploader, but I didn't want to use Flash nor Iframes or plugins and after some research I came up with the solution.
The HTML:
<form enctype="multipart/form-data">
<input name="file" type="file" />
<input type="button" value="Upload" />
</form>
<progress></progress>
First, you can do some validation if you want. For example, in the onChange event of the file:
$(':file').on('change', function() {
var file = this.files[0];
if (file.size > 1024) {
alert('max upload size is 1k')
}
// Also see .name, .type
});
Now the Ajax submit with the button's click:
$(':button').on('click', function() {
$.ajax({
// Your server script to process the upload
url: 'upload.php',
type: 'POST',
// Form data
data: new FormData($('form')[0]),
// Tell jQuery not to process data or worry about content-type
// You *must* include these options!
cache: false,
contentType: false,
processData: false,
// Custom XMLHttpRequest
xhr: function() {
var myXhr = $.ajaxSettings.xhr();
if (myXhr.upload) {
// For handling the progress of the upload
myXhr.upload.addEventListener('progress', function(e) {
if (e.lengthComputable) {
$('progress').attr({
value: e.loaded,
max: e.total,
});
}
} , false);
}
return myXhr;
}
});
});
As you can see, with HTML5 (and some research) file uploading not only becomes possible but super easy. Try it with Google Chrome as some of the HTML5 components of the examples aren't available in every browser.
I have been using the below script to upload images which happens to work fine.
<input id="file" type="file" name="file"/>
<div id="response"></div>
jQuery('document').ready(function(){
var input = document.getElementById("file");
var formdata = false;
if (window.FormData) {
formdata = new FormData();
}
input.addEventListener("change", function (evt) {
var i = 0, len = this.files.length, img, reader, file;
for ( ; i < len; i++ ) {
file = this.files[i];
if (!!file.type.match(/image.*/)) {
if ( window.FileReader ) {
reader = new FileReader();
reader.onloadend = function (e) {
//showUploadedItem(e.target.result, file.fileName);
};
reader.readAsDataURL(file);
}
if (formdata) {
formdata.append("image", file);
formdata.append("extra",'extra-data');
}
if (formdata) {
jQuery('div#response').html('<br /><img src="ajax-loader.gif"/>');
jQuery.ajax({
url: "upload.php",
type: "POST",
data: formdata,
processData: false,
contentType: false,
success: function (res) {
jQuery('div#response').html("Successfully uploaded");
}
});
}
}
else
{
alert('Not a vaild image!');
}
}
}, false);
});
I use response div to show the uploading animation and response after upload is done.
Best part is you can send extra data such as ids & etc with the file when you use this script. I have mention it extra-data as in the script.
At the PHP level this will work as normal file upload. extra-data can be retrieved as $_POST data.
Here you are not using a plugin and stuff. You can change the code as you want. You are not blindly coding here. This is the core functionality of any jQuery file upload. Actually Javascript.
You can do it in vanilla JavaScript pretty easily. Here's a snippet from my current project:
var xhr = new XMLHttpRequest();
xhr.upload.onprogress = function(e) {
var percent = (e.position/ e.totalSize);
// Render a pretty progress bar
};
xhr.onreadystatechange = function(e) {
if(this.readyState === 4) {
// Handle file upload complete
}
};
xhr.open('POST', '/upload', true);
xhr.setRequestHeader('X-FileName',file.name); // Pass the filename along
xhr.send(file);
jQuery Uploadify is another good plugin which I have used before to upload files. The JavaScript code is as simple as the following: code. However, the new version does not work in Internet Explorer.
$('#file_upload').uploadify({
'swf': '/public/js/uploadify.swf',
'uploader': '/Upload.ashx?formGuid=' + $('#formGuid').val(),
'cancelImg': '/public/images/uploadify-cancel.png',
'multi': true,
'onQueueComplete': function (queueData) {
// ...
},
'onUploadStart': function (file) {
// ...
}
});
I have done a lot of searching and I have come to another solution for uploading files without any plugin and only with ajax. The solution is as below:
$(document).ready(function () {
$('#btn_Upload').live('click', AjaxFileUpload);
});
function AjaxFileUpload() {
var fileInput = document.getElementById("#Uploader");
var file = fileInput.files[0];
var fd = new FormData();
fd.append("files", file);
var xhr = new XMLHttpRequest();
xhr.open("POST", 'Uploader.ashx');
xhr.onreadystatechange = function () {
if (xhr.readyState == 4) {
alert('success');
}
else if (uploadResult == 'success')
alert('error');
};
xhr.send(fd);
}
Simple Ajax Uploader is another option:
https://github.com/LPology/Simple-Ajax-Uploader
Example usage:
var uploader = new ss.SimpleUpload({
button: $('#uploadBtn'), // upload button
url: '/uploadhandler', // URL of server-side upload handler
name: 'userfile', // parameter name of the uploaded file
onSubmit: function() {
this.setProgressBar( $('#progressBar') ); // designate elem as our progress bar
},
onComplete: function(file, response) {
// do whatever after upload is finished
}
});
You can use
$(function() {
$("#file_upload_1").uploadify({
height : 30,
swf : '/uploadify/uploadify.swf',
uploader : '/uploadify/uploadify.php',
width : 120
});
});
To upload file asynchronously with Jquery use below steps:
step 1 In your project open Nuget manager and add package (jquery fileupload(only you need to write it in search box it will come up and install it.)) URL: https://github.com/blueimp/jQuery-File-Upload
step 2 Add below scripts in the HTML files, which are already added to the project by running above package:
jquery.ui.widget.js
jquery.iframe-transport.js
jquery.fileupload.js
step 3 Write file upload control as per below code:
<input id="upload" name="upload" type="file" />
step 4 write a js method as uploadFile as below:
function uploadFile(element) {
$(element).fileupload({
dataType: 'json',
url: '../DocumentUpload/upload',
autoUpload: true,
add: function (e, data) {
// write code for implementing, while selecting a file.
// data represents the file data.
//below code triggers the action in mvc controller
data.formData =
{
files: data.files[0]
};
data.submit();
},
done: function (e, data) {
// after file uploaded
},
progress: function (e, data) {
// progress
},
fail: function (e, data) {
//fail operation
},
stop: function () {
code for cancel operation
}
});
};
step 5 In ready function call element file upload to initiate the process as per below:
$(document).ready(function()
{
uploadFile($('#upload'));
});
step 6 Write MVC controller and Action as per below:
public class DocumentUploadController : Controller
{
[System.Web.Mvc.HttpPost]
public JsonResult upload(ICollection<HttpPostedFileBase> files)
{
bool result = false;
if (files != null || files.Count > 0)
{
try
{
foreach (HttpPostedFileBase file in files)
{
if (file.ContentLength == 0)
throw new Exception("Zero length file!");
else
//code for saving a file
}
}
catch (Exception)
{
result = false;
}
}
return new JsonResult()
{
Data=result
};
}
}
Convert file to base64 using |HTML5's readAsDataURL() or some base64 encoder. Fiddle here
var reader = new FileReader();
reader.onload = function(readerEvt) {
var binaryString = readerEvt.target.result;
document.getElementById("base64textarea").value = btoa(binaryString);
};
reader.readAsBinaryString(file);
Then to retrieve:
window.open("data:application/octet-stream;base64," + base64);
The simplest and most robust way I have done this in the past, is to simply target a hidden iFrame tag with your form - then it will submit within the iframe without reloading the page.
That is if you don't want to use a plugin, JavaScript or any other forms of "magic" other than HTML. Of course you can combine this with JavaScript or what have you...
<form target="iframe" action="" method="post" enctype="multipart/form-data">
<input name="file" type="file" />
<input type="button" value="Upload" />
</form>
<iframe name="iframe" id="iframe" style="display:none" ></iframe>
You can also read the contents of the iframe onLoad for server errors or success responses and then output that to user.
Chrome, iFrames, and onLoad
-note- you only need to keep reading if you are interested in how to setup a UI blocker when doing uploading/downloading
Currently Chrome doesn't trigger the onLoad event for the iframe when it's used to transfer files. Firefox, IE, and Edge all fire the onload event for file transfers.
The only solution that I found works for Chrome was to use a cookie.
To do that basically when the upload/download is started:
Using a cookie for this is ugly but it works.
I made a jQuery plugin to handle this issue for Chrome when downloading, you can find here
https://github.com/ArtisticPhoenix/jQuery-Plugins/blob/master/iDownloader.js
The same basic principal applies to uploading, as well.
To use the downloader ( include the JS, obviously )
$('body').iDownloader({
"onComplete" : function(){
$('#uiBlocker').css('display', 'none'); //hide ui blocker on complete
}
});
$('somebuttion').click( function(){
$('#uiBlocker').css('display', 'block'); //block the UI
$('body').iDownloader('download', 'htttp://example.com/location/of/download');
});
And on the server side, just before transferring the file data, create the cookie
setcookie('iDownloader', true, time() + 30, "/");
The plugin will see the cookie, and then trigger the onComplete callback.
You can upload simply with jQuery .ajax().
HTML:
<form id="upload-form">
<div>
<label for="file">File:</label>
<input type="file" id="file" name="file" />
<progress class="progress" value="0" max="100"></progress>
</div>
<hr />
<input type="submit" value="Submit" />
</form>
CSS
.progress { display: none; }
Javascript:
$(document).ready(function(ev) {
$("#upload-form").on('submit', (function(ev) {
ev.preventDefault();
$.ajax({
xhr: function() {
var progress = $('.progress'),
xhr = $.ajaxSettings.xhr();
progress.show();
xhr.upload.onprogress = function(ev) {
if (ev.lengthComputable) {
var percentComplete = parseInt((ev.loaded / ev.total) * 100);
progress.val(percentComplete);
if (percentComplete === 100) {
progress.hide().val(0);
}
}
};
return xhr;
},
url: 'upload.php',
type: 'POST',
data: new FormData(this),
contentType: false,
cache: false,
processData: false,
success: function(data, status, xhr) {
// ...
},
error: function(xhr, status, error) {
// ...
}
});
}));
});
Wrapping up for future readers.
You can upload files with jQuery using the $.ajax() method if FormData and the File API are supported (both HTML5 features).
You can also send files without FormData but either way the File API must be present to process files in such a way that they can be sent with XMLHttpRequest (Ajax).
$.ajax({
url: 'file/destination.html',
type: 'POST',
data: new FormData($('#formWithFiles')[0]), // The form with the file inputs.
processData: false,
contentType: false // Using FormData, no need to process data.
}).done(function(){
console.log("Success: Files sent!");
}).fail(function(){
console.log("An error occurred, the files couldn't be sent!");
});
For a quick, pure JavaScript (no jQuery) example see "Sending files using a FormData object".
When HTML5 isn't supported (no File API) the only other pure JavaScript solution (no Flash or any other browser plugin) is the hidden iframe technique, which allows to emulate an asynchronous request without using the XMLHttpRequest object.
It consists of setting an iframe as the target of the form with the file inputs. When the user submits a request is made and the files are uploaded but the response is displayed inside the iframe instead of re-rendering the main page. Hiding the iframe makes the whole process transparent to the user and emulates an asynchronous request.
If done properly it should work virtually on any browser, but it has some caveats as how to obtain the response from the iframe.
In this case you may prefer to use a wrapper plugin like Bifröst which uses the iframe technique but also provides a jQuery Ajax transport allowing to send files with just the $.ajax() method like this:
$.ajax({
url: 'file/destination.html',
type: 'POST',
// Set the transport to use (iframe means to use Bifröst)
// and the expected data type (json in this case).
dataType: 'iframe json',
fileInputs: $('input[type="file"]'), // The file inputs containing the files to send.
data: { msg: 'Some extra data you might need.'}
}).done(function(){
console.log("Success: Files sent!");
}).fail(function(){
console.log("An error occurred, the files couldn't be sent!");
});
Bifröst is just a small wrapper that adds fallback support to jQuery's ajax method, but many of the aforementioned plugins like jQuery Form Plugin or jQuery File Upload include the whole stack from HTML5 to different fallbacks and some useful features to ease out the process. Depending on your needs and requirements you might want to consider a bare implementation or either of this plugins.
Look for Handling the upload process for a file, asynchronously in here: https://developer.mozilla.org/en-US/docs/Using_files_from_web_applications
Sample from the link
<?php
if (isset($_FILES['myFile'])) {
// Example:
move_uploaded_file($_FILES['myFile']['tmp_name'], "uploads/" . $_FILES['myFile']['name']);
exit;
}
?><!DOCTYPE html>
<html>
<head>
<title>dnd binary upload</title>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<script type="text/javascript">
function sendFile(file) {
var uri = "/index.php";
var xhr = new XMLHttpRequest();
var fd = new FormData();
xhr.open("POST", uri, true);
xhr.onreadystatechange = function() {
if (xhr.readyState == 4 && xhr.status == 200) {
// Handle response.
alert(xhr.responseText); // handle response.
}
};
fd.append('myFile', file);
// Initiate a multipart/form-data upload
xhr.send(fd);
}
window.onload = function() {
var dropzone = document.getElementById("dropzone");
dropzone.ondragover = dropzone.ondragenter = function(event) {
event.stopPropagation();
event.preventDefault();
}
dropzone.ondrop = function(event) {
event.stopPropagation();
event.preventDefault();
var filesArray = event.dataTransfer.files;
for (var i=0; i<filesArray.length; i++) {
sendFile(filesArray[i]);
}
}
}
</script>
</head>
<body>
<div>
<div id="dropzone" style="margin:30px; width:500px; height:300px; border:1px dotted grey;">Drag & drop your file here...</div>
</div>
</body>
</html>
var formData=new FormData();
formData.append("fieldname","value");
formData.append("image",$('[name="filename"]')[0].files[0]);
$.ajax({
url:"page.php",
data:formData,
type: 'POST',
dataType:"JSON",
cache: false,
contentType: false,
processData: false,
success:function(data){ }
});
You can use form data to post all your values including images.
This is my solution.
<form enctype="multipart/form-data">
<div class="form-group">
<label class="control-label col-md-2" for="apta_Description">Description</label>
<div class="col-md-10">
<input class="form-control text-box single-line" id="apta_Description" name="apta_Description" type="text" value="">
</div>
</div>
<input name="file" type="file" />
<input type="button" value="Upload" />
</form>
and the js
<script>
$(':button').click(function () {
var formData = new FormData($('form')[0]);
$.ajax({
url: '@Url.Action("Save", "Home")',
type: 'POST',
success: completeHandler,
data: formData,
cache: false,
contentType: false,
processData: false
});
});
function completeHandler() {
alert(":)");
}
</script>
Controller
[HttpPost]
public ActionResult Save(string apta_Description, HttpPostedFileBase file)
{
return Json(":)");
}
Here's just another solution of how to upload file (without any plugin)
Using simple Javascripts and AJAX (with progress-bar)
HTML part
<form id="upload_form" enctype="multipart/form-data" method="post">
<input type="file" name="file1" id="file1"><br>
<input type="button" value="Upload File" onclick="uploadFile()">
<progress id="progressBar" value="0" max="100" style="width:300px;"></progress>
<h3 id="status"></h3>
<p id="loaded_n_total"></p>
</form>
JS part
function _(el){
return document.getElementById(el);
}
function uploadFile(){
var file = _("file1").files[0];
// alert(file.name+" | "+file.size+" | "+file.type);
var formdata = new FormData();
formdata.append("file1", file);
var ajax = new XMLHttpRequest();
ajax.upload.addEventListener("progress", progressHandler, false);
ajax.addEventListener("load", completeHandler, false);
ajax.addEventListener("error", errorHandler, false);
ajax.addEventListener("abort", abortHandler, false);
ajax.open("POST", "file_upload_parser.php");
ajax.send(formdata);
}
function progressHandler(event){
_("loaded_n_total").innerHTML = "Uploaded "+event.loaded+" bytes of "+event.total;
var percent = (event.loaded / event.total) * 100;
_("progressBar").value = Math.round(percent);
_("status").innerHTML = Math.round(percent)+"% uploaded... please wait";
}
function completeHandler(event){
_("status").innerHTML = event.target.responseText;
_("progressBar").value = 0;
}
function errorHandler(event){
_("status").innerHTML = "Upload Failed";
}
function abortHandler(event){
_("status").innerHTML = "Upload Aborted";
}
PHP part
<?php
$fileName = $_FILES["file1"]["name"]; // The file name
$fileTmpLoc = $_FILES["file1"]["tmp_name"]; // File in the PHP tmp folder
$fileType = $_FILES["file1"]["type"]; // The type of file it is
$fileSize = $_FILES["file1"]["size"]; // File size in bytes
$fileErrorMsg = $_FILES["file1"]["error"]; // 0 for false... and 1 for true
if (!$fileTmpLoc) { // if file not chosen
echo "ERROR: Please browse for a file before clicking the upload button.";
exit();
}
if(move_uploaded_file($fileTmpLoc, "test_uploads/$fileName")){ // assuming the directory name 'test_uploads'
echo "$fileName upload is complete";
} else {
echo "move_uploaded_file function failed";
}
?>
You can see a solved solution with a working demo here that allows you to preview and submit form files to the server. For your case, you need to use Ajax to facilitate the file upload to the server:
<from action="" id="formContent" method="post" enctype="multipart/form-data">
<span>File</span>
<input type="file" id="file" name="file" size="10"/>
<input id="uploadbutton" type="button" value="Upload"/>
</form>
The data being submitted is a formdata. On your jQuery, use a form submit function instead of a button click to submit the form file as shown below.
$(document).ready(function () {
$("#formContent").submit(function(e){
e.preventDefault();
var formdata = new FormData(this);
$.ajax({
url: "ajax_upload_image.php",
type: "POST",
data: formdata,
mimeTypes:"multipart/form-data",
contentType: false,
cache: false,
processData: false,
success: function(){
alert("successfully submitted");
});
});
});
Sample: If you use jQuery, you can do easy to an upload file. This is a small and strong jQuery plugin, http://jquery.malsup.com/form/.
var $bar = $('.ProgressBar');
$('.Form').ajaxForm({
dataType: 'json',
beforeSend: function(xhr) {
var percentVal = '0%';
$bar.width(percentVal);
},
uploadProgress: function(event, position, total, percentComplete) {
var percentVal = percentComplete + '%';
$bar.width(percentVal)
},
success: function(response) {
// Response
}
});
I hope it would be helpful
It is an old question, but still has no answer correct answer, so:
Have you tried jQuery-File-Upload ?
Here is an example from the link above -> 1 that might solve your problem:
$('#fileupload').fileupload({
add: function (e, data) {
var that = this;
$.getJSON('/example/url', function (result) {
data.formData = result; // e.g. {id: 123}
$.blueimp.fileupload.prototype
.options.add.call(that, e, data);
});
}
});
Using HTML5 and JavaScript, uploading async is quite easy, I create the uploading logic along with your html, this is not fully working as it needs the api, but demonstrate how it works, if you have the endpoint called /upload from root of your website, this code should work for you:
const asyncFileUpload = () => {
const fileInput = document.getElementById("file");
const file = fileInput.files[0];
const uri = "/upload";
const xhr = new XMLHttpRequest();
xhr.upload.onprogress = e => {
const percentage = e.loaded / e.total;
console.log(percentage);
};
xhr.onreadystatechange = e => {
if (xhr.readyState === 4 && xhr.status === 200) {
console.log("file uploaded");
}
};
xhr.open("POST", uri, true);
xhr.setRequestHeader("X-FileName", file.name);
xhr.send(file);
}<form>
<span>File</span>
<input type="file" id="file" name="file" size="10" />
<input onclick="asyncFileUpload()" id="upload" type="button" value="Upload" />
</form>Also some further information about XMLHttpReques:
The XMLHttpRequest Object
All modern browsers support the XMLHttpRequest object. The XMLHttpRequest object can be used to exchange data with a web server behind the scenes. This means that it is possible to update parts of a web page, without reloading the whole page.
Create an XMLHttpRequest Object
All modern browsers (Chrome, Firefox, IE7+, Edge, Safari, Opera) have a built-in XMLHttpRequest object.
Syntax for creating an XMLHttpRequest object:
variable = new XMLHttpRequest();
Access Across Domains
For security reasons, modern browsers do not allow access across domains.
This means that both the web page and the XML file it tries to load, must be located on the same server.
The examples on W3Schools all open XML files located on the W3Schools domain.
If you want to use the example above on one of your own web pages, the XML files you load must be located on your own server.
For more details, you can continue reading here...
</div>
You can use newer Fetch API by JavaScript. Like this:
function uploadButtonCLicked(){
var input = document.querySelector('input[type="file"]')
fetch('/url', {
method: 'POST',
body: input.files[0]
}).then(res => res.json()) // you can do something with response
.catch(error => console.error('Error:', error))
.then(response => console.log('Success:', response));
}
Advantage: Fetch API is natively supported by all modern browsers, so you don't have to import anything. Also, note that fetch() returns a Promise which is then handled by using .then(..code to handle response..) asynchronously.
A modern approach without Jquery is to use the FileList object you get back from <input type="file"> when user selects a file(s) and then use Fetch to post the FileList wrapped around a FormData object.
// The input DOM element
const inputElement = document.querySelector('input');
// Listen for a file submit from user
inputElement.addEventListener('change', () => {
const data = new FormData()
data.append('file', inputElement.files[0])
data.append('imageName', 'flower')
// Post to server
fetch('/uploadImage', {
method: 'POST',
body: data
})
});
You can do the Asynchronous Multiple File uploads using JavaScript or jQuery and that to without using any plugin. You can also show the real time progress of file upload in the progress control. I have come across 2 nice links -
The server side language is C# but you can do some modification for making it work with other language like PHP.
File Upload ASP.NET Core MVC:
In the View create file upload control in html:
<form method="post" asp-action="Add" enctype="multipart/form-data">
<input type="file" multiple name="mediaUpload" />
<button type="submit">Submit</button>
</form>
Now create action method in your controller:
[HttpPost]
public async Task<IActionResult> Add(IFormFile[] mediaUpload)
{
//looping through all the files
foreach (IFormFile file in mediaUpload)
{
//saving the files
string path = Path.Combine(hostingEnvironment.WebRootPath, "some-folder-path");
using (var stream = new FileStream(path, FileMode.Create))
{
await file.CopyToAsync(stream);
}
}
}
hostingEnvironment variable is of type IHostingEnvironment which can be injected to the controller using dependency injection, like:
private IHostingEnvironment hostingEnvironment;
public MediaController(IHostingEnvironment environment)
{
hostingEnvironment = environment;
}