Function isEmailAddress

Source: IsEmailAddress.ts

Validates whether a string is a syntactically valid email address. Optionally restricts the allowed length and permitted domains.

Validation rules:

• Length: 6–255 characters (or the configured maxLength).
• No consecutive dots (..), no dot immediately before @ (.@).
• Matches the pattern [email protected] with alphanumeric and limited punctuation.
• Domain TLD must be 2–26 alphabetic characters.

Import

import { isEmailAddress } from '@litert/utils-string';

Signature

function isEmailAddress(email: string, opts?: IEmailValidationOptions): boolean;

Parameters

• Parameter email: string

  The string to validate.

• Parameter opts?: IEmailValidationOptions

  Optional validation options. See IEmailValidationOptions.

Return Value

true if the string is a valid email address (and passes all configured constraints), false otherwise.

Scoped Types

Interface IEmailValidationOptions

Source: IsEmailAddress.ts

import type { IEmailValidationOptions } from '@litert/utils-string';

Extra options for the isEmailAddress function.

Property	Type	Default	Description
maxLength	number?	255	The maximum allowed length for the email address. If this value exceeds 255, 255 is used instead.
domains	string[]?	[]	An allowlist of permitted email domains. When provided (and non-empty), only email addresses whose domain is in this list are accepted. Comparison is case-insensitive, but only lowercase domain strings in the list are supported.

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Examples

import { isEmailAddress } from '@litert/utils-string';

isEmailAddress('[email protected]');    // true
isEmailAddress('invalid-email');       // false
isEmailAddress('[email protected]');              // false (TLD too short)

// Domain allowlist
isEmailAddress('[email protected]', { domains: ['example.com'] });  // true
isEmailAddress('[email protected]',   { domains: ['example.com'] });  // false

// Custom max length
isEmailAddress('[email protected]', { maxLength: 10 }); // true