PARSE and STRINGIFY for CSV strings. It's like JSON object but for CSV. It can also work row by row. And, if can parse strings, it can be use to parse files or streams too.
npm install csv-string
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
- Written in TypeScript
``js
import * as 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);
`
- Kael Shipman
- Mehul Mohan
- Hossam Magdy
- Rich
- Rick Huizinga
- Nicolas Thouvenin
- Stéphane Gully
- J. Baumbach
- Sam Hauglustaine
- Rick Huizinga
- doleksy1
- François Parmentier
using npm:
`bash`
npm install csv-string
or yarn
`bash`
yarn add csv-string
Converts a CSV string input to array output.
Options :
- comma String to indicate the CSV separator. (optional, default ,)quote
- String to indicate the CSV quote if need. (optional, default ")output
- String choose 'objects' or 'tuples' to change output for Array or Object. (optional, default tuples)
Example 1 :
`js`
const CSV = require('csv-string');
const parsedCsv = CSV.parse('a;b;c\nd;e;f', ';');
console.log(parsedCsv);
Output:
`json`
[
["a", "b", "c"],
["d", "e", "f"]
]
Example 2 :
`js`
const CSV = require('csv-string');
const parsedCsv = CSV.parse('a,b,c\n1,2,3\n4,5,6', { output: 'objects' });
console.log(parsedCsv);
Output:
`json`
[
{ a: '1', b: '2', c: '3' },
{ a: '4', b: '5', c: '6' }
]
If separator parameter is not provided, it is automatically detected.
Converts object input to a CSV string.
`js
import * as CSV from '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:
`txt
a,b,c
c,d,e
c,d,e
e,f,g
`
Detects the best separator.
`js
import * as CSV from '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:
`txt`
,
;
|
\t
_callback(row: array, index: number): void_
Calls callback for each CSV row/line. The Array passed to callback contains the fields of the current row.
`js
import * as CSV from 'csv-string';
const data = 'a,b,c\nd,e,f';
CSV.forEach(data, ',', function (row, index) {
console.log('#' + index + ' : ', row);
});
`
Output:
`txt`
#0 : [ 'a', 'b', 'c' ]
#1 : [ 'd', 'e', 'f' ]
_callback(row: array): void_
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.
`js
import * as CSV from 'csv-string';
const data = 'a,b,c\nd,e,f';
const index = CSV.read(data, ',', row => {
console.log(row);
});
console.log(data.slice(index));
`
Output:
`txt`
[ 'a', 'b', 'c' ]
d,e,f
_callback(rows: array): void_
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 (generally it's the end of the input string).
`js
import * as CSV from 'csv-string';
const data = 'a,b,c\nd,e,f';
const index = CSV.readAll(data, row => {
console.log(row);
});
console.log('-' + data.slice(index) + '-');
`
Output:
`txt`
[ [ 'a', 'b', 'c' ], [ 'd', 'e', 'f' ] ]
--
_callback(rows: array): void_
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.
`js
import * as CSV from 'csv-string';
const data = 'a,b,c\nd,e';
const index = CSV.readChunk(data, row => {
console.log(row);
});
console.log('-' + data.slice(index) + '-');
`
Output:
`txt`
[ [ 'a', 'b', 'c' ] ]
--
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.
`js
const stream = CSV.createStream();
stream.on('data', row => {
console.log(row);
});
process.stdin.resume();
process.stdin.setEncoding('utf8');
process.stdin.pipe(stream);
`
- clone
-
- ... do the changes, write tests
- (ensure all tests pass)yarn bench
- (to check the performance impact)
-
-
-
There is a quite basic benchmark to compare this project to other related ones, using file streams as input. See ./bench for source code.
`bash``
yarn bench
for a test file with 949,044 rows
| Package | Time | Output/Input similarity |
| -------------- | --------- | ----------------------- |
| a-csv | 6.01s | ~99% |
| csv-stream | 6.64s | ~73% |
| csv-streamer | 7.03s | ~79% |
| csv-string | 6.53s | 100% |
| fast-csv | 12.33s | 99.99% |
| nodecsv | 7.10s | 100% |