In this tutorial, I will show you way to build React.js Image Upload and Display example (with Preview) to a Rest API. The React App uses Axios and Multipart File for making HTTP requests, Bootstrap for progress bar. You also have a display list of images’ information (with download url).
More Practice:
– Typescript: Upload Image in React Typescript example (with Preview)
– Functional Component: React Hooks Image Upload with Preview example
– React Multiple Files upload example with Progress Bar
– React.js CRUD example to consume Web API
– React JWT Authentication (without Redux) example
– React + Redux: JWT Authentication example
Material UI instead:
Material UI Image Upload example with Preview, Axios & Progress Bar
Contents
- Overview
- Technology
- Rest API for File Upload & Storage
- React App for upload/download Image with preview
- Setup React Image Upload with Preview Project
- Import Bootstrap to React Image Upload and Display App
- Initialize Axios for React HTTP Client
- Create Service for File Upload
- Create Component for Upload Images
- Add Image Upload Component to App Component
- Configure Port for React Image Upload App
- Run the App
- Further Reading
- Conclusion
- Source Code
Overview
We’re gonna create a React.js Image upload with Preview example application in that user can:
- display the preview of image before uploading
- see the upload process (percentage) with progress bar
- view all uploaded images
- link to download the image when clicking on the file name
For multiple Images upload with preview, please visit:
React Multiple Images Upload with Preview example
Technology
- React 18/17/16
- Axios 0.27.2
- Bootstrap 4
Rest API for File Upload & Storage
Here is the API that our React App will work with:
Methods | Urls | Actions |
---|---|---|
POST | /upload | upload a File |
GET | /files | get List of Files (name & url) |
GET | /files/[filename] | download a File |
You can find how to implement the Rest APIs Server at one of following posts:
– Node.js Express File Upload Rest API example
– Node.js Express File Upload to MongoDB example
– Node.js Express File Upload to Google Cloud Storage example
– Spring Boot Multipart File upload (to static folder) example
Or: Spring Boot Multipart File upload (to database) example
React App for upload/download Image with preview
After building the React project is done, the folder structure will look like this:
Let me explain it briefly.
– file-upload.service provides methods to save File and get Files using Axios.
– image-upload.component contains upload form, image preview, progress bar, display of list of images with download url.
– App.js is the container that we embed all React components.
– http-common.js initializes Axios with HTTP base Url and headers.
– We configure port for our App in .env
Setup React Image Upload with Preview Project
Open cmd at the folder you want to save Project folder, run command:
npx create-react-app react-image-upload-preview
Or: yarn create react-app react-image-upload-preview
After the process is done. We create additional folders and files like the following tree:
public
src
components
image-upload.component.js
services
file-upload.service.js
App.css
App.js
index.js
package.json
Import Bootstrap to React Image Upload and Display App
Run command: npm install [email protected]
.
Or: yarn add [email protected]
Open src/App.js and modify the code inside it as following-
import React, { Component } from "react";
import "bootstrap/dist/css/bootstrap.min.css";
class App extends Component {
render() {
// ...
}
}
export default App;
Initialize Axios for React HTTP Client
Let’s install axios with command: npm install [email protected]
.
Or: yarn add [email protected]
Under src folder, we create http-common.js file with following code:
import axios from "axios";
export default axios.create({
baseURL: "http://localhost:8080",
headers: {
"Content-type": "application/json"
}
});
You can change the baseURL
that depends on REST APIs url that your Server configures.
Create Service for File Upload
This service will use Axios to send HTTP requests.
There are 2 functions:
upload(file)
: POST form data with a callback for tracking upload progressgetFiles()
: GET list of Files’ information
services/file-upload.service.js
import http from "../http-common";
class FileUploadService {
upload(file, onUploadProgress) {
let formData = new FormData();
formData.append("file", file);
return http.post("/upload", formData, {
headers: {
"Content-Type": "multipart/form-data",
},
onUploadProgress,
});
}
getFiles() {
return http.get("/files");
}
}
export default new FileUploadService();
– First we import Axios as http
from http-common.js.
– Inside upload()
method, we use FormData
to store key-value pairs. It helps to build an object which corresponds to HTML form using append()
method.
– We pass onUploadProgress
to exposes progress events. This progress event are expensive (change detection for each event), so you should only use when you want to monitor it.
– We call Axios post()
to send an HTTP POST for uploading a File to Rest APIs Server and get()
method for HTTP GET request to retrieve all stored files.
Create Component for Upload Images
Let’s create a Image Upload UI with Preview, Progress Bar, Card, Button and Message.
First we create a React component template and import FileUploadService
:
components/upload-files.component.js
import React, { Component } from "react";
import UploadService from "../services/file-upload.service";
export default class UploadImages extends Component {
constructor(props) {
}
render() {
}
}
Then we define the state inside constructor()
method:
export default class UploadImages extends Component {
constructor(props) {
super(props);
...
this.state = {
currentFile: undefined,
previewImage: undefined,
progress: 0,
message: "",
imageInfos: [],
};
}
}
Next we define selectFile()
method which helps us to get the selected Files from <input type="file" >
element later.
export default class UploadImages extends Component {
...
selectFile(event) {
this.setState({
currentFile: event.target.files[0],
previewImage: URL.createObjectURL(event.target.files[0]),
progress: 0,
message: ""
});
}
We use event.target.files[0]
for accessing current File as the first Item.
We’re gonna use URL.createObjectURL()
static method to get the image preview URL as previewImage
. This method produces a DOMString
including a URL describing the object provided in the parameter. The URL life is tied to the document in the window on which it was created.
We call UploadService.upload()
method on the currentFile
with a callback. So create following upload()
method:
export default class UploadImages extends Component {
...
upload() {
this.setState({
progress: 0,
});
UploadService.upload(this.state.currentFile, (event) => {
this.setState({
progress: Math.round((100 * event.loaded) / event.total),
});
})
.then((response) => {
this.setState({
message: response.data.message,
});
return UploadService.getFiles();
})
.then((files) => {
this.setState({
imageInfos: files.data,
});
})
.catch((err) => {
this.setState({
progress: 0,
message: "Could not upload the image!",
currentFile: undefined,
});
});
}
The progress will be calculated basing on event.loaded
and event.total
.
If the transmission is done, we call UploadService.getFiles()
to get the images’ information and assign the result to imageInfos
state, which is an array of {name, url}
objects.
We also need to do this work in componentDidMount()
method:
export default class UploadImages extends Component {
...
componentDidMount() {
UploadService.getFiles().then((response) => {
this.setState({
imageInfos: response.data,
});
});
}
Now we implement the render function of the Upload File UI. Add the following code inside render()
:
export default class UploadImages extends Component {
...
render() {
const {
currentFile,
previewImage,
progress,
message,
imageInfos,
} = this.state;
return (
<div>
<div className="row">
<div className="col-8">
<label className="btn btn-default p-0">
<input type="file" accept="image/*" onChange={this.selectFile} />
</label>
</div>
<div className="col-4">
<button
className="btn btn-success btn-sm"
disabled={!currentFile}
onClick={this.upload}
>
Upload
</button>
</div>
</div>
{currentFile && (
<div className="progress my-3">
<div
className="progress-bar progress-bar-info progress-bar-striped"
role="progressbar"
aria-valuenow={progress}
aria-valuemin="0"
aria-valuemax="100"
style={{ width: progress + "%" }}
>
{progress}%
</div>
</div>
)}
{previewImage && (
<div>
<img className="preview" src={previewImage} alt="" />
</div>
)}
{message && (
<div className="alert alert-secondary mt-3" role="alert">
{message}
</div>
)}
<div className="card mt-3">
<div className="card-header">List of Files</div>
<ul className="list-group list-group-flush">
{imageInfos &&
imageInfos.map((img, index) => (
<li className="list-group-item" key={index}>
<a href={img.url}>{img.name}</a>
</li>
))}
</ul>
</div>
</div>
);
}
}
We allow only image format, so the input
element will have accept="image/*"
attribute.
In the code above, we use Bootstrap Progress Bar:
.progress
as a wrapper- inner
.progress-bar
to indicate the progress .progress-bar
requiresstyle
to set the width by percentage.progress-bar
also requiresrole
and some aria attributes to make it accessible- label of the progress bar is the text within it
The preview of uploading image is shown: <img className="preview" src={previewImage} alt="" />
To display List of uploaded images, we iterate over imageInfos
array using map()
function. On each file item, we use img.url
as href
attribute and img.name
for showing text.
Add Image Upload Component to App Component
Open App.js, import and embed the UploadImages
Component tag.
import React from "react";
import "./App.css";
import "bootstrap/dist/css/bootstrap.min.css";
import UploadImages from "./components/image-upload.component";
function App() {
return (
<div className="container">
<h3>bezkoder.com</h3>
<h4>React Image Upload with Preview</h4>
<div className="content">
<UploadImages />
</div>
</div>
);
}
export default App;
App.css
.container{
width: 600px !important;
margin: 20px;
}
.content {
margin: 20px 0;
}
.preview {
max-width: 200px;
}
Configure Port for React Image Upload App
Because most of HTTP Server use CORS configuration that accepts resource sharing restricted to some sites or ports, and if you use the following Project for making Server:
– Node.js Express File Upload Rest API example
– Node.js Express File Upload to MongoDB example
– Node.js Express File Upload to Google Cloud Storage example
– Spring Boot Multipart File upload (to static folder) example
Or: Spring Boot Multipart File upload (to database) example
You need to configure port for our App.
In project folder, create .env file with following content:
PORT=8081
So our app will run at port 8081.
Run the App
You can find how to implement the Rest APIs Server at one of following posts:
– Node.js Express File Upload Rest API example
– Node.js Express File Upload to MongoDB example
– Node.js Express File Upload to Google Cloud Storage example
– Spring Boot Multipart File upload (to static folder) example
Or: Spring Boot Multipart File upload (to database) example
Run this React File Upload Axios: npm start
.
Or: yarn start
.
Open Browser with url http://localhost:8081/
and check the result.
Further Reading
- https://github.com/axios/axios
- React Component
- Bootstrap 4 Progress
- React.js CRUD example to consume Web API
- React JWT Authentication (without Redux) example
Conclusion
Today we’re learned how to build an example for Image upload and display (with Preview) using React.js and Axios. We also provide the ability to show preview, list of images, upload progress bar using Bootstrap, and to download image from the server.
Happy Learning! See you again.
If you want to upload multiple images at once like this:
You can find the instruction here:
React Multiple Images Upload with Preview example
Or using Material UI instead:
Material UI Image Upload example with Preview, Axios & Progress Bar
Source Code
The source code for the React Client is uploaded to Github.
– Using Functional Component: React.js Image Upload with Preview example
– Or Typescript: Upload Image in React Typescript example (with Preview)
Please provide its functional version . thanks
Hi, here you are:
React.js Image Upload with Preview using Hooks
That’s what I was looking for, what a tutorial! Thanks!
thanks
Hi. thanks for this tutorial. I download the projet from github and when I try to upload I get this message : Could not upload the image! . I’ve check in the console and I get this messsage :Uncaught (in promise) Error: Request failed with status code 404. I don’t know if I have to create a folder ‘upload/’. thanks.
Hi, you need to create upload folder first 🙂
where we have to create upload folder –
under src or outside src
Thanks!
Thanks!
Thank you for this comprehensive and simple tutorial!
Hello! This is my first visit to your blog but I think this programming website is one of the best! Clear and comprehensive tutorial.