rn-date

rn-date is a zero-dependency TypeScript library which fixes the date parsing issues in React Native with Android.

Background

React Native on Android has inconsistent date parsing behavior compared to iOS and web. The native Date constructor may parse date strings differently depending on the platform and format. This library provides consistent, reliable date parsing across all platforms.

Features

• Zero runtime dependencies - Minimal bundle size impact
• TypeScript support - Full type definitions included
• Consistent parsing - Same behavior across iOS, Android, and web
• Multiple format support:
  • Date-only: YYYY-MM-DD
  • DateTime: YYYY-MM-DD HH:MM:SS
  • ISO 8601: YYYY-MM-DDTHH:MM:SS.sssZ
• Utility methods - Convenient formatting and validation

Installation

yarn add rn-date
# or
npm install rn-date

Usage

Basic Import

import { RnDate } from 'rn-date';

Creating Dates

// Current date and time
const now = new RnDate();

// Date-only format (parsed as UTC)
const date = new RnDate('2022-01-01');

// DateTime with space separator (parsed as local time)
const dateTime = new RnDate('2022-01-01 17:04:03');

// ISO 8601 format (UTC with timezone)
const isoDate = new RnDate('2022-01-01T00:00:00.000Z');

Using with Date Methods

RnDate extends the native Date class, so all standard Date methods are available:

const date = new RnDate('2022-01-01 17:04:03');

// Standard Date methods work as expected
date.getFullYear();  // 2022
date.getMonth();     // 0 (January)
date.getDate();      // 1
date.getHours();     // 17
date.getMinutes();   // 4
date.getSeconds();   // 3

// Format methods
date.toISOString();      // "2022-01-01T16:04:03.000Z" (UTC)
date.toDateString();     // "Sat Jan 01 2022"
date.toString();         // Full date string

// Timestamp
date.getTime();          // 1641056643000

API Reference

Constructor

new RnDate(dateString?: string)

Creates a new RnDate instance.

Parameters:

• dateString (string | undefined) - The date string to parse

Supported formats:

• YYYY-MM-DD - Date only (parsed as UTC)
• YYYY-MM-DD HH:MM:SS - DateTime (parsed as local time)
• YYYY-MM-DDTHH:MM:SS.sssZ - ISO 8601 format (UTC)
• undefined or null - Current date and time

Throws:

• TypeError - If dateString is not a string or undefined

Examples:

// Current date
const now = new RnDate();
const alsoNow = new RnDate(undefined);

// Specific date (UTC)
const date = new RnDate('2022-01-01');

// Specific datetime (local time)
const dateTime = new RnDate('2022-01-01 17:04:03');

// ISO format (UTC)
const isoDate = new RnDate('2022-01-01T00:00:00.000Z');

// Invalid date returns Invalid Date
const invalid = new RnDate('invalid-date');
console.log(invalid.toString()); // "Invalid Date"

Methods

isValid(): boolean

Checks if this RnDate represents a valid date.

Returns: boolean - true if the date is valid, false otherwise

Example:

const validDate = new RnDate('2022-01-01');
validDate.isValid(); // true

const invalidDate = new RnDate('invalid');
invalidDate.isValid(); // false

toDateFormat(): string

Formats the date as a string in the format YYYY-MM-DD (UTC).

Returns: string - The formatted date string

Example:

const date = new RnDate('2022-01-01 17:04:03');
date.toDateFormat(); // "2022-01-01"

toDateTimeFormat(): string

Formats the date and time as a string in the format YYYY-MM-DD HH:MM:SS (local time).

Returns: string - The formatted datetime string

Example:

const date = new RnDate('2022-01-01 17:04:03');
date.toDateTimeFormat(); // "2022-01-01 17:04:03"

Platform Differences

The native Date constructor has platform-specific behaviors:

| Format | iOS/Web | Android (without fix) | Android (with RnDate) | |--------|---------|----------------------|----------------------| | YYYY-MM-DD | UTC | Local (inconsistent) | UTC (consistent) | | YYYY-MM-DD HH:MM:SS | Local | Local | Local | | YYYY-MM-DDTHH:MM:SS.sssZ | UTC | UTC | UTC |

RnDate ensures consistent behavior across all platforms.

License

MIT