JSFiddle - React, Tailwind, and code Playground

JavaScript

var CSV = [
    '"1","val1","val2","val3","val4"',
    '"2","val1","val2","val3","val4"',
    '"3","val1","val2","val3","val4"'
  ].join('\n');

window.URL = window.webkitURL || window.URL;

var contentType = 'text/csv';

var csvFile = new Blob([CSV], {type: contentType});

var a = document.createElement('a');
a.download = 'my.csv';
a.href = window.URL.createObjectURL(csvFile);
a.textContent = 'Download CSV';

a.dataset.downloadurl = [contentType, a.download, a.href].join(':');

document.body.appendChild(a);