File Helper

getFileExtension

import { FileHelper } from '@oardi/ts-utils';

FileHelper.getFileExtension('archive.TXT');
// '.txt'

Files without an extension and dotfiles such as .env return an empty string.

Read files

const text = await FileHelper.readAsText(file);
const buffer = await FileHelper.readAsArrayBuffer(file);
const event = await FileHelper.readAsDataUrl(file);
const dataUrl = event.target?.result;

The read methods require a browser environment and reject their promise when the underlying FileReader fails.

formatFileSize

FileHelper.formatFileSize(1536);
// '1.5 KB'

FileHelper.formatFileSize(1536, 2, 'Bytes');
// '1536 Bytes'

Supported explicit units are Bytes, KB, MB, GB, and TB. Automatic formatting uses TB for values beyond that unit. The byte value must be a non-negative safe integer. Decimal precision must be an integer from 0 through 100; invalid values throw a RangeError. An explicit unit is also respected for zero, for example formatFileSize(0, 2, 'KB') returns '0 KB'.

isWithinSizeLimit

const maxBytes = 10 * 1024 * 1024;

FileHelper.isWithinSizeLimit(file, maxBytes);
// true when the file is at most 10 MB

The limit must be a non-negative safe integer expressed in bytes.