csv-string

What is csv-string?

The csv-string npm package provides simple utilities for parsing and stringifying CSV (Comma-Separated Values) data. It is lightweight and easy to use, making it suitable for basic CSV operations.

What are csv-string's main functionalities?

Stringify

This feature converts an array of arrays into a CSV string. The code sample demonstrates how to convert a 2D array into a CSV formatted string.

const CSVString = require('csv-string');
const data = [['name', 'age'], ['Alice', 30], ['Bob', 25]];
const csv = CSVString.stringify(data);
console.log(csv);

Parse

This feature parses a CSV string into an array of arrays. The code sample shows how to convert a CSV formatted string into a 2D array.

const CSVString = require('csv-string');
const csv = 'name,age\nAlice,30\nBob,25';
const data = CSVString.parse(csv);
console.log(data);

Detect

This feature detects the delimiter used in a CSV string. The code sample demonstrates how to detect the delimiter in a given CSV string.

const CSVString = require('csv-string');
const csv = 'name,age\nAlice,30\nBob,25';
const delimiter = CSVString.detect(csv);
console.log(delimiter);

Encode

This feature encodes an array into a CSV string. The code sample shows how to encode a single array into a CSV formatted string.

const CSVString = require('csv-string');
const data = ['Alice', '30'];
const encoded = CSVString.encode(data);
console.log(encoded);

Decode

This feature decodes a CSV string into an array. The code sample demonstrates how to decode a single CSV formatted string into an array.

const CSVString = require('csv-string');
const csv = 'Alice,30';
const decoded = CSVString.decode(csv);
console.log(decoded);

Other packages similar to csv-string

csv-parser

The csv-parser package is a streaming CSV parser that is more suitable for handling large CSV files. It provides a more robust and efficient way to parse CSV data compared to csv-string, especially for large datasets.

papaparse

PapaParse is a powerful CSV parser that can handle large files and supports various configurations. It offers more advanced features like asynchronous parsing, web workers, and the ability to handle malformed CSV data, making it more versatile than csv-string.

fast-csv

fast-csv is a comprehensive CSV parser and formatter that supports both reading and writing CSV data. It is designed for high performance and can handle large datasets efficiently, offering more features and better performance compared to csv-string.

README

Javascript CSV Strings

Parse and Stringify for CSV strings.

• API similar to the JSON parser (CSV.parse and CSV.stringify).
• Can also work row by row.
• Can also be used to parse strings from readable streams (e.g. file streams).
• tolerant with the weird data
• ES6 support

	import { CSV } from 'csv-string';

	// with String
	const arr = CSV.parse('a,b,c\na,b,c');
	const str = CSV.stringify(arr);


	// with Stream
	const stream = CSV.createStream();
	stream.on('data', (rows) => {
			process.stdout.write(CSV.stringify(rows, ','));
	})
	process.stdin.pipe(stream);

Contributors

• Nicolas Thouvenin
• Stéphane Gully
• J. Baumbach
• Sam Hauglustaine
• Rick Huizinga
• doleksy1
• François Parmentier

Installation

With npm:

$ npm install csv-string

Tests

Use mocha to run the tests.

$ npm install mocha
$ mocha test

API Documentation

parse(input : String, [separator : String], [quote : String]) : Object

Converts a CSV string input to array output.

	var CSV = require('csv-string'),
	 arr = CSV.parse('a,b,c\na,b,c');

	console.log(arr);

Output:

[ [ 'a', 'b', 'c' ], [ 'a', 'b', 'c' ] ]

If separator parameter is not provided, it is automatically detected.

stringify(input : Object, [separator : String]) : String

Converts object input to a CSV string.

	var CSV = require('csv-string');

	console.log(CSV.stringify(['a', 'b', 'c']));
	console.log(CSV.stringify([['c', 'd', 'e'], ['c','d','e']]));
	console.log(CSV.stringify({a:'e', b:'f', c:'g'}));

Output:

a,b,c

c,d,e
c,d,e

e,f,g

detect(input : String) : String

Detects the best separator.

	var CSV = require('csv-string');

	console.log(CSV.detect('a,b,c'));
	console.log(CSV.detect('a;b;c'));
	console.log(CSV.detect('a|b|c'));
	console.log(CSV.detect('a\tb\tc'));

Output:

,
;
|
\t

forEach(input : String, sep : String, quo : String, callback : Function)

forEach(input : String, sep : String, callback : Function)

forEach(input : String, callback : Function)

callback(row : Array, index : Number) : undefined

Calls callback for each CSV row/line. The Array passed to callback contains the fields of the current row.

	var CSV = require('csv-string');
    var data = 'a,b,c\nd,e,f';
	CSV.forEach(data, ',', function(row, index) {
		console.log('#' + index + ' : ', row);
	});

Output:

#0 :  [ 'a', 'b', 'c' ]
#1 :  [ 'd', 'e', 'f' ]

read(input : String, sep : String, quo : String, callback : Function) : Number

read(input : String, sep : String, callback : Function) : Number

read(input : String, callback : Function) : Number

callback(row : Array) : undefined

Calls callback when a CSV row is read. The Array passed to callback contains the fields of the row.
Returns the first offset after the row.

	var CSV = require('csv-string');
    var data = 'a,b,c\nd,e,f';
	var index = CSV.read(data, ',', function(row) {
		console.log(row);
	});
    console.log(data.slice(index));

Output:

[ 'a', 'b', 'c' ]
d,e,f

readAll(input : String, sep : String, quo : String, callback : Function) : Number

readAll(input : String, sep : String, callback : Function) : Number

readAll(input : String, callback : Function) : Number

callback(rows : Array) : undefined

Calls callback when all CSV rows are read. The Array passed to callback contains the rows of the file.
Returns the offset of the end of parsing (generaly it's the end of the input string).

	var CSV = require('csv-string');
    var data = 'a,b,c\nd,e,f';
	index = CSV.readAll(data, function(row) {
		console.log(row);
	});
    console.log('-' + data.slice(index) + '-');

Output:

[ [ 'a', 'b', 'c' ], [ 'd', 'e', 'f' ] ]
--

readChunk(input : String, sep : String, quo : String, callback : Function) : Number

readChunk(input : String, sep : String, callback : Function) : Number

readChunk(input : String, callback : Function) : Number

callback(rows : Array) : undefined

Calls callback when all CSV rows are read. The last row could be ignored, because the remainder could be in another chunk. The Array passed to callback contains the rows of the file. Returns the offset of the end of parsing. If the last row is ignored, the offset will point to the beginnning of the row.

	var CSV = require('csv-string');
    var data = 'a,b,c\nd,e';
	index = CSV.readChunk(data, function(row) {
		console.log(row);
	});
    console.log('-' + data.slice(index) + '-');

Output:

[ [ 'a', 'b', 'c' ] ]
--

createStream(options : Object) : WritableStream

createStream() : WritableStream

Create a writable stream for CSV chunk. Options are :

• separator : To indicate the CSV separator. By default is auto (see the detect function)
• quote** : To indicate the CSVquote.

Example : Read CSV file from the standard input.

	var stream = CSV.createStream();

	stream.on('data', function (row) {
	     console.log(row);
	  }
	)

	process.stdin.resume();
	process.stdin.setEncoding('utf8');
	process.stdin.pipe(stream);

Related projects

• https://npmjs.org/browse/keyword/csv
• http://www.uselesscode.org/javascript/csv/
• https://github.com/archan937/csonv.js

Benchmark

I made a very basic benchmark to compare this project to other related projects, using file streams as input. See ./bench for source code.

the test

	time node ./SCRITPNAME.js >/dev/null

the result

Package	Input equal Output	Time for ~1 200 000 rows
a-csv	almost	0m13.903s
csv-streamer	yes	0m15.599s
csv-stream	yes	0m17.265s
csv-string	yes	0m15.432s
fast-csv	no	-
nodecsv	yes	0m22.129s

License

MIT/X11