partial-csv-reader

𝄜 Partial CSV Reader

A library to parse any part of a large CSV file

Installation

npm i partial-csv-reader

Usage

Create an instance of CsvReader from a File/Blob instance of the CSV file. You can get the file in the browser from an <input type="file" />:

const csvFile = fileInputElement.files[0];
const csvReader = new CsvReader(csvFile);

Next, you will need an instance of CsvRow that represents a single row in the CSV. You have three options:

• Getting the first row
• Getting the last row
• Getting a row anywhere in between by its byte / percentage offset in the file

You can use any, based on your preference:

// Get the `CsvRow` of the first row
csvRow = await csvReader.getFirstRow();

// Get the `CsvRow` of the last row
csvRow = await csvReader.getLastRow();

// Get a row around the 50th percentile of the file
csvRow = await csvReader.getRowAtPercent(50);

Now that you have the first row, you can navigate forward or backward from here to get other rows:

// Get next row
csvRow = await csvRow.nextRow();

// Get previous row
csvRow = await csvRow.prevRow();

Finally, you can get cell data on any desired row:

cells = await csvRow.getCells();
// ["Year", "Make", "Model"]

For a more detailed usage, see src/example/index.ts. To see it in action, you can open example/app.html in your browser after running npm run build.