downloadAsCSV.js

var downloadAsCSV = function (arr, filename) {
  csvRows = [];
  for (var i = 0, l = arr.length; i < l; i++) {
    csvRows.push(arr[i].join('#'));
  }

  var csvString = csvRows.join('%0A');
  csvString = csvString.replace(/ /g, '__');

  var a         = document.createElement('a');
  a.href        = 'data:attachment/csv,' + csvString;
  a.target      = '_blank';
  a.download    = filename + '.csv';

  document.body.appendChild(a);
  a.click();
};