export-to-csv

In Node.js, instead of using the download function (which is for browsers), you should use generateCsv to create the data and then write it to the file system using node:fs. You may need to convert the output using asString and Buffer to create a writable Uint8Array.

import { mkConfig, generateCsv, asString } from "export-to-csv";
import { writeFile } from "node:fs";
import { Buffer } from "node:buffer";

const csvConfig = mkConfig({ useKeysAsHeaders: true });

const mockData = [
  {
    name: "Rouky",
    date: "2023-09-01",
    percentage: 0.4,
    quoted: '"Pickles"',
  },
  {
    name: "Keiko",
    date: "2023-09-01",
    percentage: 0.9,
    quoted: '"Cactus"',
  },
];

const csv = generateCsv(csvConfig)(mockData);
const filename = `${csvConfig.filename}.csv`;
const csvBuffer = new Uint8Array(Buffer.from(asString(csv)));

// Write the csv file to disk
writeFile(filename, csvBuffer, (err) => {
  if (err) throw err;
  console.log("file saved: ", filename);
});

In a browser environment, you can use mkConfig to merge your options with defaults, generateCsv to convert an array of objects into CSV data, and download to trigger a file download. The library uses ES modules.

import { mkConfig, generateCsv, download } from "export-to-csv";

// mkConfig merges your options with the defaults
const csvConfig = mkConfig({ useKeysAsHeaders: true });

const mockData = [
  {
    name: "Rouky",
    date: "2023-09-01",
    percentage: 0.4,
    quoted: '"Pickles"',
  },
  {
    name: "Keiko",
    date: "2023-09-01",
    percentage: 0.9,
    quoted: '"Cactus"',
  },
];

// Converts your Array<Object> to a CsvOutput based on the configs
const csv = generateCsv(csvConfig)(mockData);

// Trigger download on a button click
const csvBtn = document.querySelector("#csv") as HTMLButtonElement;
csvBtn.addEventListener("click", () => download(csvConfig)(csv));

When using the library, you can provide a ConfigOptions object to customize the CSV generation process. If you do not provide certain options, the library uses the following default values:

// Example of overriding defaults
const myConfig = {
  fieldSeparator: ";",
  showTitle: true,
  title: "Custom Report",
  replaceUndefinedWith: "N/A"
};

When using the library, you can provide a ConfigOptions object to control the structure and formatting of the generated CSV/TSV.

Key configuration properties include:

• filename: The name of the file to be generated.
• fieldSeparator: The character used to separate fields (e.g., , or ;).
• quoteStrings: Boolean to determine if strings should be wrapped in quotes.
• quoteCharacter: The character used for quoting strings.
• decimalSeparator: The character used for decimal points.
• showColumnHeaders: Whether to include the header row.
• showTitle: Whether to include a title at the top of the file.
• title: The title text to display.
• fileExtension: The file extension to use (e.g., .csv).
• mediaType: The MIME type of the output (see MediaType for options).
• useBom: Whether to include a Byte Order Mark (BOM).
• columnHeaders: An array of ColumnHeader objects to define custom headers.
• useKeysAsHeaders: If true, uses the object keys from the data as headers.
• boolDisplay: An object mapping boolean values to display strings: { true: 'Yes', false: 'No' }.
• replaceUndefinedWith: A value (string, boolean, or null) to use when a field is undefined.
• escapeFormulas: Boolean to escape characters that might trigger spreadsheet formulas.

Note: The useTextFile option is deprecated and will be removed in version 2.x.x. Use fileExtension instead.

const options: ConfigOptions = {
  filename: 'export.csv',
  fieldSeparator: ',',
  showColumnHeaders: true,
  mediaType: MediaType.csv,
  boolDisplay: { true: 'TRUE', false: 'FALSE' },
  replaceUndefinedWith: ''
};