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Custom Validation Interface: If you need a boolean-style validation method, consider creating a custom interface like IValidatable with a bool IsValid method for implementation by relevant classes.

Example of Custom Validation Interface in C#

Here's an example of using a custom validation interface in C#:

1. Define the Interface:

C#

public interface IValidatable
{
    bool IsValid { get; }
}

This interface defines a single property IsValid that returns a boolean value indicating the validity of the implementing object.

2. Implement the Interface:

C#

public class Person : IValidatable
{
    public string Name { get; set; }
    public int Age { get; set; }

    public bool IsValid
    {
        get
        {
            return !string.IsNullOrEmpty(Name) && Age >= 18;
        }
    }
}

The Person class implements the IValidatable interface and provides its own implementation for the IsValid property. This property checks for a non-empty name and age greater than or equal to 18, returning true if both conditions are met.

3. Usage with Validation Utility:

C#

public static class ValidationUtil
{
    public static void Validate(IValidatable obj)
    {
        if (!obj.IsValid)
        {
            throw new ValidationException("Object is not valid.");
        }
    }
}

public class Example
{
    public void ValidatePerson(Person person)
    {
        ValidationUtil.Validate(person);
        // Only proceed if validation passes
        Console.WriteLine("Person is valid: {0}", person.Name);
    }
}

The ValidationUtil class defines a Validate method that accepts an IValidatable object. This method throws a ValidationException if the object's IsValid property is false.

The Example class demonstrates how to use the ValidatePerson method with a Person object. This method first validates the person using ValidationUtil.Validate and then proceeds only if the validation passes.

Benefits:

• Decoupled Validation Logic: By separating validation logic into the interface, you promote code reusability and maintainability.
• Flexible Validation Implementation: Different classes can implement their own validation rules through the interface, allowing for diverse validation requirements.
• Centralized Validation Handling: The ValidationUtil class provides a central location for handling validation logic, promoting code consistency.

This example provides a basic framework for utilizing custom validation interfaces in C#. You can further extend this concept by adding additional validation rules or creating different validation interfaces for specific purposes.