mr-crocs-adventures/js/FileLoader.js

export default class FileLoader
{
    constructor(filename)
    {
        this.filename = filename;
        this.content = '';

        this.onLoad = () => {};
    }

    getContent()
    {
        return this.content;
    }

    loadContent()
    {
        let request = new XMLHttpRequest();

        request.onreadystatechange = () => {
            if (request.status === 200 && request.readyState === 4) {
                this.content = request.responseText;
                this.onLoad(this.content);
            }
        };

        request.open('GET', this.filename, false);
        request.send();
    }
}