Validation

This is a validation framework which should help to do basic validations like max length, required etc.

Features

Following Validators are available

Validator	Descriptions
BIC	Bic code check if it has the right format
email	Verifies the email format
equals	Compare if two strings are equal. Used for Password check
lowercase	Checks if the string is lowercase
max_length	Maximal length a string can have
max_value	Max value of a double
min_value	Min value of a double
one_digit	Must be one digit
phone	International format of a phone number
required	Value must be not null and contain some chars
special_character	Checks if a string contains any special characters
uppercase	String must be uppercase

Getting started

This package uses easy_localization for error messages. Consumer can of course override all the translations globally and define custom message per validator.

Usage

This example demonstrates check of the double value. Entered value by user is in this example 50, but max allowed value is 10.

ValidationBuilder<double>()
    .required()
    .maxValue(10)
    .validate(50)

Check the mail

final validationResult = ValidationBuilder<String>().email().validate("mario#mydomain.com");
expect(validationResult, "This is not a valid email address.",
reason: "Email is not valid, so a message must be returned");

Custom error message

final validationResult = ValidationBuilder<String>().email("Mail not ok").validate("mario#mydomain.com");
expect(validationResult, "Mail not ok", reason: "Custom message must be used");

Translations

in order to generate translation files just run

dart run easy_localization:generate --source-dir assets/translations  --source-file en.json --output-dir lib -f keys -o locale_keys_validation.g.dart

Customize translations

ValidationBuilder.configuration = Configuration(
              translation: (translationKey, dynamic currentValue, String? additionalParam, dynamic configValue) {
    if (translationKey == LocaleKeysValidation.validation_error_value_required) {
      return requiredTrans;
    }
    return null;
});

Last modified: 05 March 2024