Object Array to CSV, with optional header & escaped comma & double-quotes

objArrayToCsv.js

// Inspired by https://stackoverflow.com/a/11257124/5288481
// Assumes all objects have the same keys
function objArrayToCsv(objArray, header=true) {
  // parse to object if not already one
  let array = typeof objArray != 'object' ? JSON.parse(objArray) : objArray;
  let str = '';

  // header row
  if (header && array.length >= 1) {
    let line = '';
    for (var key in array[0]) {
      if (line != '') {
        line += ',';
      }
      line += key;
    }
    str += line + '\r\n';
  }

  for (var i = 0; i < array.length; i++) {
    let line = '';
    for (var index in array[i]) {
      if (line != '') {
        line += ',';
      }
      let field = array[i][index];
      if (typeof(field) === 'string' && field.match('[,"]')) {
        if (field.includes('"')) {
          // " becomes ""
          field = field.replace('"', '""');
        }
        // surround in double quotes
        field = `"${field}"`;
      }
      line += field;
    }
    str += line + '\r\n';
  }

  return str;
}