TransformValidator<T> class

TransformValidator extends BaseValidator to transform a value before applying a validator.

Parameters:

transformer A function that transforms the value before validation.
validator The validator to apply to the transformed value.
checkNullOrEmpty Whether to check if the value is null or empty. This is set to false by default.

Inheritance

TransformValidator.new(T? transformer(T? value), FormFieldValidator<T> validator): Constructor for the transform validator.
const

checkNullOrEmpty → bool: Whether to check if the value is null or empty.
finalinherited
errorText → String?: The error message returned if the value is invalid.
no setterinherited
hashCode → int: The hash code for this object.
no setterinherited
runtimeType → Type: A representation of the runtime type of the object.
no setterinherited
transformer → T? Function(T? value): A function that transforms the value before validation.
final
validator → FormFieldValidator<T>: The validator to apply to the transformed value.
final

isNullOrEmpty(T? valueCandidate) → bool: Checks if the value is null or empty. Returns true if the value is null or empty, otherwise false. The value is considered empty if it is a String, Iterable, or Map and it is empty or contains only whitespace characters. If the value is not a String, Iterable, or Map, it is considered empty if it is null.
inherited
noSuchMethod(Invocation invocation) → dynamic: Invoked when a nonexistent method or property is accessed.
inherited
toString() → String: A string representation of this object.
inherited
validate(T? valueCandidate) → String?: Validates the value and checks if it is null or empty.
override
validateValue(T? valueCandidate) → String?: Validates the value. Returns null if the value is valid, otherwise an error message. Call validate() instead of this method when using the validator.
override