Class AsyncPredicateValidatorRule<T, TProperty>

Namespace: REslava.Result

Assembly: REslava.Result.dll

A validation rule that uses an async predicate function to validate a property of an entity. Supports async lambda expressions for asynchronous validation scenarios.

public class AsyncPredicateValidatorRule<T, TProperty> : IValidatorRuleAsync<T>, IValidatorRule<T>

Type Parameters

T: The type of entity to validate.
TProperty: The type of the property being validated.

Inheritance: object

AsyncPredicateValidatorRule<T, TProperty>

Implements: IValidatorRuleAsync<T>

IValidatorRule<T>

Inherited Members: object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

object.ToString()

Extension Methods: ValidationExtensions.EnsureNotNull<TCollection>(TCollection?, string, string?)

Examples

// Create an async rule using lambda
var rule = new AsyncPredicateValidatorRule<User, string>(
    u => u.Email,
    "UniqueEmail",
    "Email already exists",
    async email => await EmailService.IsUniqueAsync(email)
);

// Use the rule
var result = await rule.ValidateAsync(user);

Constructors

AsyncPredicateValidatorRule(Func<T, TProperty>, string, string, Func<TProperty, Task<bool>>)

Initializes a new instance of the AsyncPredicateValidatorRule.

public AsyncPredicateValidatorRule(Func<T, TProperty> propertySelector, string ruleName, string errorMessage, Func<TProperty, Task<bool>> validator)

Parameters

propertySelector Func<T, TProperty>: Function to select the property to validate.
ruleName string: The name of the validation rule.
errorMessage string: The error message if validation fails.
validator Func<TProperty, Task<bool>>: The async validation predicate function.

Examples

var rule = new AsyncPredicateValidatorRule<User, string>(
    u => u.Email,
    "UniqueEmail",
    "Email already exists",
    async email => await EmailService.IsUniqueAsync(email)
);

Properties

ErrorMessage

Gets the default error message for this validation rule.

public string ErrorMessage { get; }

Property Value

string

Name

Gets the name of the validation rule.

public string Name { get; }

Property Value

string

Methods

ValidateAsync(T)

Validates the specified entity using the async predicate function.

public Task<ValidationResult<T>> ValidateAsync(T entity)

Parameters

entity T: The entity to validate.

Returns

Task<ValidationResult<T>>: A ValidationResult indicating success or failure.

Examples

var user = new User("test@example.com", 25);
var result = await rule.ValidateAsync(user);

if (result.IsValid)
{
    Console.WriteLine("Validation passed");
}
else
{
    Console.WriteLine($"Validation failed: {result.ValidationErrors.First().Message}");
}