How to upload a file without a form using JavaScript?
Sometimes, developers may need to upload files without using JavaScript forms. Normally, we create a form to get data and files from the user, but in this tutorial, we will learn to get the files from the user without a form and send it to the backend.
Using FormData() objects and Ajax requests
The FormData object allows us to store form data in key-value pairs. We need to use constructor to initialize variables. We can allow the user to upload a file using HTML input and store that file in the form data. We can then send the form data to the backend.
grammar
Users can use the FormData() object and ajax request according to the following syntax to upload files without using a form.
form_data.append("file", uploadedFile);
$.ajax({
url: "URL",
method: "POST",
data: form_data,
});
In the above syntax, we use the append() method to add a file to the form data object. Additionally, we use ajax() to send data to the API.
Example
In the example below, we have created a file input in HTML using the tag. In JavaScript, whenever a user uploads a file, we access it and add it to the form_data object.
After that, we use ajax to send the file to the API via POST request.
<html>
<head>
<script src = "https://cdnjs.cloudflare.com/ajax/libs/jquery/3.6.3/jquery.min.js"></script>
</head>
<body>
<h3>Using the <i>FormData object and ajax request</i> to upload a file without using the form data in JavaScript</h3>
<input type = "file" name = "file" id = "file_input" />
<div id = "content"> </div>
<script>
$(document).on('change', '#file_input', function () {
let uploadedFile = document.getElementById('file_input').files[0];
var form_data = new FormData();
form_data.append("file", uploadedFile);
$.ajax({
url: "URL",
method: "POST",
data: form_data,
});
});
</script>
</body>
</html>
Use jQuery simple upload plug-in
jQuery includes a simple upload plugin that we can use to send files to the API. We need to add the CDN of the simple upload plugin to the
section to use it. If a developer is using the application, they can use NPM commands to install the package.grammar
Users should follow the following syntax to upload form-less files using JavaScript using the jQuery Simple Upload plugin.
$(this).simpleUpload("URL", {
start: function (file) {
//upload started
},
});
In the above syntax, we call the simpleUpload() function of the simple upload plug-in to upload files.
Example
In the example below, we added the path to the simpleUpload.min.js file in the
section. We added a "change" event on the file input. In the callback function, we call the simpleUpload() function with the file input as reference. We pass this object as the second parameter of the simpleUpload() function with the key and callback function as values.<html>
<head>
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.6.3/jquery.min.js"></script>
<script src= "https://cdn.jsdelivr.net/npm/jquery-simpleupload@1.1.0/simpleUpload.min.js"> </script>
</head>
<body>
<h3>Using the <i>jQuery simple upload</i> plugin to upload the file without using the form</h3>
<input type = "file" name = "file" id = "file_input">
<div id = "content"> </div>
<script>
$('#file_input').change(function () {
$(this).simpleUpload("abcd.php", {
start: function (file) {
//upload started
content.innerHTML = "upload started";
},
});
});
</script>
</body>
</html>
Users learned two different ways to upload files without using forms in JavaScript. We used FormData object and ajax() method in the first method. In the second method, we used Jquery's simple upload plugin.
The above is the detailed content of How to upload a file without a form using JavaScript?. For more information, please follow other related articles on the PHP Chinese website!
Hot AI Tools
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Undress AI Tool
Undress images for free
Clothoff.io
AI clothes remover
Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!
Hot Article
Hot Tools
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
Hot Topics
1387
52
What should I do if I encounter garbled code printing for front-end thermal paper receipts?
Apr 04, 2025 pm 02:42 PM
Frequently Asked Questions and Solutions for Front-end Thermal Paper Ticket Printing In Front-end Development, Ticket Printing is a common requirement. However, many developers are implementing...
Who gets paid more Python or JavaScript?
Apr 04, 2025 am 12:09 AM
There is no absolute salary for Python and JavaScript developers, depending on skills and industry needs. 1. Python may be paid more in data science and machine learning. 2. JavaScript has great demand in front-end and full-stack development, and its salary is also considerable. 3. Influencing factors include experience, geographical location, company size and specific skills.
Demystifying JavaScript: What It Does and Why It Matters
Apr 09, 2025 am 12:07 AM
JavaScript is the cornerstone of modern web development, and its main functions include event-driven programming, dynamic content generation and asynchronous programming. 1) Event-driven programming allows web pages to change dynamically according to user operations. 2) Dynamic content generation allows page content to be adjusted according to conditions. 3) Asynchronous programming ensures that the user interface is not blocked. JavaScript is widely used in web interaction, single-page application and server-side development, greatly improving the flexibility of user experience and cross-platform development.
How to merge array elements with the same ID into one object using JavaScript?
Apr 04, 2025 pm 05:09 PM
How to merge array elements with the same ID into one object in JavaScript? When processing data, we often encounter the need to have the same ID...
How to achieve parallax scrolling and element animation effects, like Shiseido's official website?
or:
How can we achieve the animation effect accompanied by page scrolling like Shiseido's official website?
Apr 04, 2025 pm 05:36 PM
Discussion on the realization of parallax scrolling and element animation effects in this article will explore how to achieve similar to Shiseido official website (https://www.shiseido.co.jp/sb/wonderland/)...
The difference in console.log output result: Why are the two calls different?
Apr 04, 2025 pm 05:12 PM
In-depth discussion of the root causes of the difference in console.log output. This article will analyze the differences in the output results of console.log function in a piece of code and explain the reasons behind it. �...
Is JavaScript hard to learn?
Apr 03, 2025 am 12:20 AM
Learning JavaScript is not difficult, but it is challenging. 1) Understand basic concepts such as variables, data types, functions, etc. 2) Master asynchronous programming and implement it through event loops. 3) Use DOM operations and Promise to handle asynchronous requests. 4) Avoid common mistakes and use debugging techniques. 5) Optimize performance and follow best practices.
How to implement panel drag and drop adjustment function similar to VSCode in front-end development?
Apr 04, 2025 pm 02:06 PM
Explore the implementation of panel drag and drop adjustment function similar to VSCode in the front-end. In front-end development, how to implement VSCode similar to VSCode...
