Validator class

A utility class for Flutter Form validation. Provides methods that return a validator function suitable for TextFormField.

Example:

TextFormField(
  validator: Validator.compose([
    Validator.required(errorMessage: 'Email is required'),
    Validator.email(errorMessage: 'Please enter a valid email'),
  ]),
)

Constructors

Validator()

Properties

hashCode → int

The hash code for this object.

no setter, inherited

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

Methods

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

toString() → String

A string representation of this object.

inherited

Operators

operator ==(Object other) → bool

The equality operator.

inherited

Static Methods

alpha({String errorMessage = 'Only letters are allowed'}) → String? Function(String?)

Ensures the string consists only of letters.

alphanumeric({String errorMessage = 'Only letters and numbers are allowed'}) → String? Function(String?)

Ensures the string consists only of letters and numbers.

ascii({String errorMessage = 'Only ASCII characters are allowed'}) → String? Function(String?)

Ensures the string only contains ASCII characters.

base32({String errorMessage = 'Please enter a valid Base32 encoded string'}) → String? Function(String?)

Ensures the string is a valid Base32 encoded string.

base58({String errorMessage = 'Please enter a valid Base58 encoded string'}) → String? Function(String?)

Ensures the string is a valid Base58 encoded string.

base64({bool urlSafe = false, String errorMessage = 'Please enter a valid Base64 encoded string'}) → String? Function(String?)

Ensures the string is Base64 encoded.

boolean({String errorMessage = 'Please enter true or false'}) → String? Function(String?)

Ensures the string represents a boolean value.

byteLength(int min, {int? max, String errorMessage = 'Length is out of range'}) → String? Function(String?)

Ensures the string's UTF-8 byte length falls within a range.

compose(Iterable<String? Function(String?)> validators) → String? Function(String?)

Runs validators in order and returns the first error, or null if all pass.

contains(String seed, {bool ignoreCase = false, int minOccurrences = 1, String errorMessage = 'Required text is missing'}) → String? Function(String?)

Ensures the string contains the seed substring.

creditCard({String errorMessage = 'Please enter a valid credit card number'}) → String? Function(String?)

Ensures the string is a valid credit card.

date({String errorMessage = 'Please enter a valid date'}) → String? Function(String?)

Ensures the string is a valid date.

decimal({String errorMessage = 'Please enter a valid decimal number'}) → String? Function(String?)

Ensures the string represents a decimal number.

email({String errorMessage = 'Please enter a valid email address'}) → String? Function(String?)

Ensures the string is a valid email.

equals(String comparison, {String errorMessage = 'Values do not match'}) → String? Function(String?)

Ensures the string matches the comparison string exactly.

float({double? min, double? max, String errorMessage = 'Please enter a valid number'}) → String? Function(String?)

Ensures the string is a finite floating-point number.

fqdn({String errorMessage = 'Please enter a valid domain name'}) → String? Function(String?)

Ensures the string is a fully qualified domain name.

hexadecimal({String errorMessage = 'Please enter a valid hexadecimal number'}) → String? Function(String?)

Ensures the string is a hexadecimal number.

hexColor({String errorMessage = 'Please enter a valid hex color (e.g. #ff0000)'}) → String? Function(String?)

Ensures the string is a valid hex color.

inList(Iterable<String> allowed, {String errorMessage = 'Value is not allowed'}) → String? Function(String?)

Ensures the string is one of the allowed values.

integer({String errorMessage = 'Please enter a valid whole number'}) → String? Function(String?)

Ensures the string is a valid integer.

ip({int? version, String errorMessage = 'Please enter a valid IP address'}) → String? Function(String?)

Ensures the string is a valid IP address.

json({String errorMessage = 'Please enter valid JSON'}) → String? Function(String?)

Ensures the string is valid JSON.

jwt({String errorMessage = 'Please enter a valid JWT'}) → String? Function(String?)

Ensures the string is a valid JSON Web Token.

latLong({String errorMessage = 'Please enter valid coordinates'}) → String? Function(String?)

Ensures the string is a valid latitude,longitude pair.

length(int min, {int? max, String errorMessage = 'Length is out of range'}) → String? Function(String?)

Ensures the string length falls within the specified range.

lowercase({String errorMessage = 'Must be lowercase'}) → String? Function(String?)

Ensures the string is entirely lowercase.

macAddress({String errorMessage = 'Please enter a valid MAC address'}) → String? Function(String?)

Ensures the string is a valid MAC address.

matches(Pattern pattern, {String errorMessage = 'Invalid format'}) → String? Function(String?)

Ensures the string matches the given pattern.

md5({String errorMessage = 'Please enter a valid MD5 hash'}) → String? Function(String?)

Ensures the string is a valid MD5 hash.

mongoId({String errorMessage = 'Please enter a valid MongoDB ObjectId'}) → String? Function(String?)

Ensures the string is a valid MongoDB ObjectId.

numeric({String errorMessage = 'Please enter a valid number'}) → String? Function(String?)

Ensures the string is a valid number.

octal({String errorMessage = 'Please enter a valid octal number'}) → String? Function(String?)

Ensures the string is an octal number.

phone({String errorMessage = 'Please enter a valid phone number'}) → String? Function(String?)

Ensures the string is a valid phone number.

port({String errorMessage = 'Please enter a valid port number'}) → String? Function(String?)

Ensures the string is a valid port number.

required({String errorMessage = 'This field is required'}) → String? Function(String?)

Ensures the field is not null or empty.

semVer({String errorMessage = 'Please enter a valid semantic version'}) → String? Function(String?)

Ensures the string is a valid Semantic Version.

slug({String errorMessage = 'Please enter a valid slug'}) → String? Function(String?)

Ensures the string is a valid URL slug.

strongPassword({int minLength = 8, int minLowercase = 1, int minUppercase = 1, int minNumbers = 1, int minSymbols = 1, String errorMessage = 'Password is not strong enough'}) → String? Function(String?)

Ensures the string is a strong password.

uppercase({String errorMessage = 'Must be uppercase'}) → String? Function(String?)

Ensures the string is entirely uppercase.

url({String errorMessage = 'Please enter a valid URL'}) → String? Function(String?)

Ensures the string is a valid URL.

uuid({String errorMessage = 'Please enter a valid UUID'}) → String? Function(String?)

Ensures the string is a valid UUID.