A crude but working upload example

upload.js

import React, { Component } from "react";
import axios from "axios";

export default class extends Component {
    constructor(props) {
        super(props);
        this.state = {
            upload_file: null
        };
    }

    async upload(event) {
        const formData = new FormData();
        
        formData.append("uploadedFile", event.target.files[0]);

        const config = { headers: { "Content-Type": "multipart/form-data" } };

        const data = await axios.post("https://yourapi.com/upload/", formData, config);
    }

    render() {
        return (
            <div>
                <input
                    value={this.state.upload_file}
                    onChange={event => this.upload(event)}
                    accept=".png"
                    type="file"
                />
            </div>
        );
    }
}