dsv.formatRows()

dsv.formatRows(rows)

Formats the specified array of array of string rows as delimiter-separated values, returning a string. This operation is the reverse of dsv.parseRows. Each row will be separated by a newline (\n), and each column within each row will be separated by the delimiter (such as a comma, ,). Values that contain either the delimiter, a double-quote (") or a newline will be escaped using double-quotes.

To convert an array of objects to an array of arrays while explicitly specifying the columns, use array.map. For example:

var string = d3.csvFormatRows(data.map(function(d, i) {
  return [
    d.year.getFullYear(), // Assuming d.year is a Date object.
    d.make,
    d.model,
    d.length
  ];
}));

If you like, you can also array.concat this result with an array of column names to generate the first row:

var string = d3.csvFormatRows([[
    "year",
    "make",
    "model",
    "length"
  ]].concat(data.map(function(d, i) {
  return [
    d.year.getFullYear(), // Assuming d.year is a Date object.
    d.make,
    d.model,
    d.length
  ];
})));