.contains()

Passes when value.contains(substring) is true. Case-sensitive.

Signature

StringValidator<O> contains(String substring, {String? message, MessageBuilder? messageBuilder})

Parameters

Parameter	Type	Meaning
substring	String	The text that has to appear. params['substring'].
message	String?	Replaces the default error message.
messageBuilder	MessageBuilder?	Builds the message from the issue. message wins when both are given. See Message builders.

Issue

Code missingSubstring. Default message: value does not contain "@". value is replaced by the field name when there is one.

Code generation

@Contains(s). Put the annotation on the constructor parameter or the field.

Example

Hand-written

final handle = l.string().contains('@');

Generated

@Contains('@') required String handle, // l.string().contains("@").required()

handle.validate(input)+1-1

1. +valid: '[email protected]'
2. -invalid: 'a'value does not contain "@"