A simple Javascript function that takes a two-dimensional array and converts it to a downloaded CSV file.

QuickArrayToCSV.js

const fieldHeaders = ["First Name", "Last Name", "City", "State", "Country", "Phone Number"];
let data = [["Tom", "Stevens", "Seattle", "WA", "USA", "123-123-1234"], ["Mike", "Williams", "Detroit", "MI", "USA", "234-234-2345"], ["Janie", "Jackson", "Vancouver", "BC", "Canada", "987-977-9876"]];
data.unshift(fieldHeaders);

function createCSV(data) { 
  let csvContent = "data:text/csv;charset=utf-8,";
  data.forEach((dataArray, index) => {
    let dataStr = dataArray.join(',');
    csvContent += index < data.length ? dataStr + '\n' : dataStr;
  });
  let encodedData = encodeURI(csvContent);
  let link = document.createElement('a');
  link.setAttribute('href', encodedData);
  link.setAttribute('download', 'my_csv.csv');
  document.body.appendChild(link);
  link.click();
}

createCSV(data);