Validity.DataAnnotation 2.1.3

Table of content

• Installing
• Usage
• Result Message
• Result Errors

Installation

dotnet add package Resulver

Usage

 public Result<int> Sum(int a, int b)
 {
     var sum = a + b;

     return new Result<int>(sum);
 }

 public void Writer()
 {
     var result = Sum(3, 5);

     Console.WriteLine(result.Content);
 } 

Result Message

public Result<User> AddUser(User user)
{
    // implementation

    return new Result<User>(user, message: "User Created");
}

public void Writer()
{
    var user = new User();

    var result = AddUser(user);

    Console.WriteLine(result.Message);
}

Result Errors

public class UserNotFoundError() : ResultError(message: "User not found");
public class UserIdIsNotValidError() : ResultError(message:   "User ID is not valid");

public Result RemoveUser(int userId)
{
    //Implementation



    return new UserNotFoundError();

    //or for multiple errors
    return new Result(new UserNotFoundError(), new UserIdIsNotValidError());
}

public void Writer()
{
    var result = RemoveUser(1);

    if (result.IsFailure)
    {
        foreach (var error in result.Errors)
        {
            Console.WriteLine(error.Message);
        }
    }
}

1. Install package

dotnet add package AutoValidator.DataAnnotation

2. Create Class

public class MyClass
{
     [Phone]
     public string PhoneNumber { get; set; }
     public NestedClass Nested { get; set; }
}

public class NestedClass
{
     [MaxLength(5)]
     public string Title { get; set; }
}

3. Add validator to service container

in Program.cs

 builder.Services.AddObjectValidator();

4. Inject validator to yout controller

[ApiController]
[Route("api/[controller]")]
public class MyController : ControllerBase
{
    readonly IObjectValidator _validator;

    public MyController(IObjectValidator validator)
    {
        _validator = validator;
    }
}

5. Use validator

[HttpPost]
public IActionResult AddUser(MyClass myClass)
{
    var validationErrors = _validator.Validate(myClass);

    if (validationErrors.Count != 0)
    {
        //DO SOMETHING
    }
}