Validation rule that compares a value to a constant.
Implements: IValidationRule
Description
The ValueComparisonRule class allows you to create a validation rule that compares a value to a constant.
Constructors
Creates a new validation rule and sets its values.
ValueComparisonRule(String operation, dynamic value)
- operation: String - comparison operation: "==" ("=", “EQ”), “!= " ("<>”, “NE”); “<"/">” (“LT”/“GT”), “<="/">=” (“LE”/“GE”); “LIKE”.
- value: dynamic - constant value to compare to
Instance methods
validate
Validates a given value against this rule.
@override
void performValidation(String? path, dynamic value, List<ValidationResult> results)
- path: String? - dot notation path to the value.
- schema: Schema - schema this rule is called from
- value: dynamic - value to be validated.
- results: List<ValidationResult> - list with validation results to add new results.
Examples
var schema = Schema()
.withRule( ValueComparisonRule('EQ', 1));
schema.validate(1); // Result: no errors
schema.validate(2); // Result: 2 is not equal to 1