如何从 controller 获取 id 并将其传递给 c# 中的另一个 controller

Question

I am using entity framework on a WebAPI based on .NET Core and i need to get an id from a controller and pass it to another controller where i need to store in in the database. First of all, in the Controller1 i have a method Create() where i return a user and there is the moment when the id is assigned.

public User Create(User user, string password)
    {
        // validation
        if (string.IsNullOrWhiteSpace(password))
            throw new AppException("Password is required");

        if (_context.Users.Any(x => x.Username == user.Username))
            throw new AppException("Username \"" + user.Username + "\" is already taken");

        byte[] passwordHash, passwordSalt;
        CreatePasswordHash(password, out passwordHash, out passwordSalt);

        user.PasswordHash = passwordHash;
        user.PasswordSalt = passwordSalt;


        _context.Users.Add(user);
        _context.SaveChanges();
     
        return user;
    }

In the last step, the 'user' which is returned already have the property id set. After that i need to get the user.Id and pass it to the Controller2 which is like this:

 [HttpPost]
    public async Task<ActionResult<PaymentDetail>> PostPaymentDetail(PaymentDetail paymentDetail)
    {    
        _context.PaymentDetails.Add(paymentDetail);
        await _context.SaveChangesAsync();

        return CreatedAtAction("GetPaymentDetail", new { id = paymentDetail.PMId}, paymentDetail);
    }

I think i need something like user.Id = paymentDetail.userId.

Here is the Controller1 from where i call the Create() method:

 [HttpPost("register")]
    public IActionResult Register([FromBody]RegisterModel model)
    {
        // map model to entity
        var user = _mapper.Map<User>(model);
        try
        {
            // create user
            _userService.Create(user, model.Password);
            
            return Ok();
        }
        catch (AppException ex)
        {
            // return error message if there was an exception
            return BadRequest(new { message = ex.Message });
        }
    }

Answer 1

There are a few ways to do what you want. Typically you would take advantage of the wonderful Dependency Injection capabilities built right in to .NET Core and then implement the Repository Pattern .

It looks like you are half-way there.

Your controllers should do the bare-minimum (simply calls your DI services) and your services should do all the heavy lifting.

You have a lot of business logic in your controllers. That logic should be abstracted to DI services. This way it's easy to share that logic among all your controllers by simply injecting them via controller constructor.

Typically you don't call one controller in your project from another. If you wanted to do that, you would have to make an actual Http request (using HttpClient ) and that is a waste of resources especially when you have the power of Dependency Injection at your fingertips.

The link I provided shows some good examples of what I am talking about, but if you'd like a more specific example, I would be more than happy to provide one.

Answer 2

I think you just can use call controller.

OneController.cs

public class OneController : Controller
{
    public IActionResult Index()
    {
        var id = CreateUser();

        TwoController con = new TwoController();
        var returnvalue = con.Register(id);

        return View();
    }

    public int CreateUser()
    {
        return 1;
    }
}

TwoController.cs

public class TwoController : Controller
{
    public string Register(int id)
    {
        if (id == 1)
            return "Success";
        else
            return "Fail";
    }
}

Result