random_string_generator

An easy to use, customizable and secure random string generator.

Can also be used as a password generator by using the following option:

mustHaveAtLeastOneOfEach = true

NEW (2.0.0) > PasswordStrengthChecker, an util to check how strong a password generated with RandomStringGenerator is. The checkStrength static function will return one of the 4 enum values available: VERY_WEAK, WEAK, GOOD and STRONG, based on the RegEx patterns provided to it.

Usage

Basic usage

var generator = RandomStringGenerator(
    fixedLength: 10,
  );

print(generator.generate());

This will generate a random string of length 10 which contains:

• random uppercase and lowercase alpha characters
• random digits
• random symbols

You can change the properties on the generator object

var generator = RandomStringGenerator(
    fixedLength: 10,
  );
generator.fixedLength = 5;

print(generator.generate());

WARNING: The call to .generate() will throw RandomStringGeneratorException with a String message property when the parameters are logically wrong! You should try-catch and print the message to see what was wrong.

Examples when it will throw:

• If you set minLength > maxLength.
• If you set only minLength or maxLength, but you do not set the other one.
• If you set both fixedLength and minLength + maxLength.
• If you set hasDigits = true, hasSymbols = true and mustHaveAtLeastOneOfEach = true, but you set the length to be 1 instead of minimum 2.

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Advanced usage

var generator = RandomStringGenerator(
    hasAlpha: true,
    alphaCase: AlphaCase.UPPERCASE_ONLY,
    hasDigits: false,
    hasSymbols: true,
    minLength: 10,
    maxLength: 25,
    mustHaveAtLeastOneOfEach: true,
  );

print(generator.generate());

This will generate a random string of length between 10 (included) and 25 (included) which is guaranteed to contain at least one of below:

• random uppercase-only alpha characters
• random digits
• random symbols

Note: In order for the at least one of each feature to work, you must provide a minimum length at least equal to the sum of the true boolean values (hasAlpha, hasDigits, hasSymbols) and the alphaCase.

Examples, assuming mustHaveAtLeastOneOfEach = true:

1. If hasAlpha, hasDigits, hasSymbols are all set to true and alphaCase is set to AlphaCase.LOWERCASE_ONLY, the total length must be 3 in order to cover all cases.

2. If hasAlpha, hasDigits, hasSymbols are all set to true and alphaCase is set to AlphaCase.MIXED_CASE, the total length must be (3 + 1 from MIXED_CASE, which means both lower and upper) = 4 in order to cover all cases.

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You can also provide custom lists of characters

var generator = RandomStringGenerator(
    hasAlpha: true,
    alphaCase: AlphaCase.MIXED_CASE,
    hasDigits: true,
    hasSymbols: false,
    minLength: 5,
    maxLength: 10,
    mustHaveAtLeastOneOfEach: false,
    customUpperAlphabet = ['A', 'B', 'X', 'Z'],
    customLowerAlphabet = ['w', 'n', 'h'],
    customDigits = ['1', '2', '3'], // digits as String
    customSymbols = ['?', '@'],
  );

print(generator.generate());

For more information, please see the documentation.

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License

MIT