Swift Validators

String (and more) validation for iOS.

ReactiveSwift + SwiftValidators

Want to use SwiftValidators with ReactiveSwift? SwiftValidatorsReactiveExtensions provides a set of extensions that play well with ValidatingProperty.


SwiftValidators is available on CocoaPods for iOS 9.0+, Xcode 8 and Swift 3.0


target 'MyProject' do
pod 'SwiftValidators'

It is also available through SPM:

import PackageDescription

let package = Package(
name: "MyProject",
targets: [],
dependencies: [
.Package(url: "https://github.com/gkaimakas/SwiftValidators.git",
majorVersion: 6)



Validation is done using the apply function of a Validator.
You can create a Validator manually or you can use on of the already available via static functions in the Validator class.

A Validator's apply function accepts an input as a nullable value that conforms to the StringConvertible protocol. By default String, NSString, Int, Float, Double and Bool conform to StringConvertible.

You can specify the Validator's behaviour when it's input is nil if you are using the static Validator function by setting the nilResponse parameter to either true or false. By default nilResponse is set to false.

Validator.exactLength(3).apply("abc") //returns true

Validator.exactLength(3).apply(true) //returns false (the string representation of true is 'true')

Validator.exactLength(3).apply(nil) //returns false since `nilResponse` is set to false by default

Valuidator.exactLength(3, nilResponse: true).apply(nil) //returns true since we set nilResponse to true

For more examples on how to call each validator you can look at the unit tests.

Logical Operators

You can combine operators using the logical AND, logical OR and Logical NOT operators ( &&, || and ! respectively).

let combinedANDValidator = Validator.required() && Validator.isTrue()

The combinedANDValidator will be true only when the value is not empty and "true"

let combinedORValidator = Validator.isTrue() || Validators.isFalse()

The combinedORValidator will be true if the value is "true" or "false", otherwise it will be false.

let reversedValidator = !Validator.isTrue()

The reversedValidator will be false when the value equals "true" and true for all other values.

Available Validators

Name Description Type Arguments Example
contains checks if it is contained in the seed func String, Bool(nilReponse=false) Validator.contains("some seed").apply("ee")
equals checks if it equals another func String, Bool(nilReponse=false) Validator.equals("aa").apply("aa")
exactLength checks if it has the exact length func Int, Bool(nilReponse=false) Validator.exactLength(2).apply("aa")
isASCII checks if it is valid ascii string func Bool(nilReponse=false) Validator.isASCII().apply("SDGSFG")
isAfter checks if it is after the date func String, String, Bool(nilReponse=false) Validator.isAfter("23/07/2015", format: "dd/MM/yyyy").apply("24/07/2015")
isAlpha checks if it has only letters func Bool(nilReponse=false) Validator.isAlpha().apply("abc")
isAlphanumeric checks if it has letters and numbers only func Bool(nilReponse=false) Validator.isAlphanumeric().apply("abc123")
isBase64 checks if it a valid base64 string func Bool(nilReponse=false) Validator.isBase64().apply("some string")
isBefore checks if it is before the date func String, String, Bool(nilReponse=false) Validator.isBefore("25/09/1987", format: "dd/MM/yyyy").apply("29/03/1994")
isBool checks if it is boolean func Bool(nilReponse=false) Validator.isBool().apply("true")
isCreditCard checks if it is a credit card number func Bool(nilReponse=false) Validator.isCreditCard().apply("123")
isDate checks if it is a valid date func String, Bool(nilReponse=false) Validator.isDate("dd/MM/yyyy").apply("25/09/1987")
isEmail checks if it is an email func Bool(nilReponse=false) Validator.isEmail().apply("[email protected]")
isEmpty checks if it is an empty string func Bool(nilReponse=false) Validator.isEmpty().apply("")
isFQDN checks if it is fully qualified domain name func FQDNOptions or empty, Bool(nilReponse=false) Validator.isFQDN().apply("ABC")
isFalse checks if it is false func Bool(nilReponse=false) Validator.isFalse().apply("false")
isFloat checks if it is a float number func Bool(nilReponse=false) Validator.isFloat().apply("2.3e24")
isHexColor checks if it is a valid hex color func Bool(nilReponse=false) Validator.isHexColor().apply("#fafafa")
isHexadecimal checks if it is a hexadecimal value func Bool(nilReponse=false) Validator.isHexadecimal().apply("abcdef")
isIP checks if it is a valid IP (4 |6) func Bool(nilReponse=false) Validator.isIP().apply("")
isIPv4 checks if it is a valid IPv4 func Bool(nilReponse=false) Validator.isIPv4().apply("")
isIPv6 checks if it is a valid IPv6 func Bool(nilReponse=false) Validator.isIPv6().apply("::")
isISBN checks if it is a valid ISBN func ISBN, Bool(nilReponse=false) Validator.isISBN(.v13).apply("asdf")
isIn checks if the value exists in the supplied array func Array, Bool(nilReponse=false) Validator.isIn(["a","b","c"]).apply("a")
isInt checks if it is a valid integer func Bool(nilReponse=false) Validator.isInt().apply("123")
isLowercase checks if it only has lowercase characters func Bool(nilReponse=false) Validator.isLowercase().apply("asdf")
isMongoId checks if it a hexadecimal mongo id func Bool(nilReponse=false) Validator.isMongoId()("adfsdffsg")
isNumeric checks if it is numeric func Bool(nilReponse=false) Validator.isNumeric().apply("+123")
isPhone checks if it is a valid phone func Phone, Bool(nilReponse=false) Validator.isPhone(.el_GR).apply("6944848966")
isPostalCode checks it is a valid postal code func PostalCode, Bool(nilResponse=false) Validator.isPostalCode(.GR).apply("30 006")
isTrue checks if it is true func Bool(nilReponse=false) Validator.isTrue().apply("true")
isURL checks if it is a valid URL func Bool(nilReponse=false) Validator.isURL().apply("http://www.google.com")
isUUID checks if it is a valid UUID func Bool(nilReponse=false) Validator.isUUID().apply("243-124245-2235-123")
isUppercase checks if has only uppercase letter func Bool(nilReponse=false) Validator.isUppercase().apply("ABC")
maxLength checks if the length does not exceed the max length func Int, Bool(nilReponse=false) Validator.maxLength(2).apply("ab")
minLength checks if the length isn't lower than func Int, Bool(nilReponse=false) Validator.minLength(1).apply("213")
required checks if it is not an empty string func Bool(nilReponse=false) Validator.required().apply("")
regex checks that the value matches the regex from start to finish func String, Bool(nilReponse=false) Validator.regex(pattern).apply("abcd")

*FQDNOptions is a class that is used on isFQDN for configuration purposes. It can be instantiated like this:

FQDNOptions(requireTLD: Bool, allowUnderscores: Bool, allowTrailingDot: Bool)