C# — DTO (Data Transfer Object)

DTO is a method provide an efficient way to Hide specific properties that clients don’t need to receive

Example 👨‍💻

1- Suppose we have Users’ information stored in a database and is represented a class Calling User.

2 -However, we don’t want to return all this information to the client. We wants to return just the user’s first name, last name, and email address.

3- The DTO class can then be used in your API controller to return the necessary information.

// 1-
public class User
{
    public int Id { get; set; }
    public string FirstName { get; set; }
    public string LastName { get; set; }
    public DateTime BirthDate { get; set; }
    public string Email { get; set; }
    public string PhoneNumber { get; set; }
}

// 2-

public class UserDto
{
    public string FirstName { get; set; }
    public string LastName { get; set; }
    public string Email { get; set; }
}

// 3-

[HttpGet("api/users/{id}")]
public IActionResult GetUser(int id)
{
    var user = database.Users.SingleOrDefault(user => user.Id == id);
    if (user == null)
    {
        return NotFound();
    }

    var userDto = new UserDto
    {
        FirstName = user.FirstName,
        LastName = user.LastName,
        Email = user.Email
    };

    return Ok(userDto);
}