如何获取登录用户的用户名并进行比较以获取ID

Question

I want to be able to get the username of the logged in user in my C# ASP.net application so I can get the ID of that user. I then want to perform an edit so they can apply to be part of an appointment.

With my current code, I click the link and I just get a HTTP 400 error. I have debugged this and the ID is coming through as the correct value. Is there any reason that its not being attached to the url?

// GET: 
    public ActionResult VolunteerCeremony(int? id)
    {
        if (id == null)
        {
            return new HttpStatusCodeResult(HttpStatusCode.BadRequest);
        }

        string userName = string.Empty;

        //if (System.Web.HttpContext.Current != null &&
        //    System.Web.HttpContext.Current.User.Identity.IsAuthenticated)
        //{
        //    System.Web.Security.MembershipUser usr = System.Web.Security.Membership.GetUser();
        //    if (usr != null)
        //    {
        //        userName = usr.UserName;
        //    }
        //}

        var getVolunteerId = (from u in db.Volunteers
                              where WebSecurity.CurrentUserName == u.Username
                              select u.VolunteerId).FirstOrDefault();


        Volunteer volunteer = db.Volunteers
            .Include(p => p.Appointments)
            .Where(i => getVolunteerId == id)
            .FirstOrDefault();

        if (volunteer == null)
        {
            return HttpNotFound();
        }
        PopulateAssignedCeremonyData(volunteer);
        return View(volunteer);
    }

    // POST: /Player/Edit/5
    // To protect from overposting attacks, please enable the specific properties you want to bind to, for 
    // more details see http://go.microsoft.com/fwlink/?LinkId=317598.
    [HttpPost]
    [ValidateAntiForgeryToken]
    public ActionResult VolunteerCeremony(int? id, string[] selectedOptions)
    {
        if (id == null)
        {
            return new HttpStatusCodeResult(HttpStatusCode.BadRequest);
        }

        var getVolunteerId = (from u in db.Volunteers
                              where WebSecurity.CurrentUserName == u.Username
                              select u.VolunteerId).FirstOrDefault();


        var updateVolunteerWithCeremony = db.Volunteers
            .Include(p => p.Appointments)
            .Where(i => getVolunteerId == id)
            .Single();

        try
        {
            UpdateVolunteerCeremonies(selectedOptions, updateVolunteerWithCeremony);

            db.Entry(updateVolunteerWithCeremony).State = EntityState.Modified;
            db.SaveChanges();

            return RedirectToAction("Index");
        }
        catch (RetryLimitExceededException /* dex */)
        {
            //Log the error (uncomment dex variable name and add a line here to write a log.
            ModelState.AddModelError("", "Unable to save changes. Try again, and if the problem persists, see your system administrator.");
        }


        PopulateAssignedCeremonyData(updateVolunteerWithCeremony);
        return View(updateVolunteerWithCeremony);
    }

EDIT This is where I'm calling the method

else if(Request.IsAuthenticated && HttpContext.Current.User.IsInRole("Volunteer"))
                    {
                        <li>@Html.ActionLink("Appointments", "Create", "Appointments")</li>
                        <li>@Html.ActionLink("Join Ceremony", "VolunteerCeremony", "Volunteers")</li>
                    }

EDIT 2 Here's my ViewModel that I used for the many to many relationship I have:

public class VolunteerCeremonyVM
{
    public int AppointmentId { get; set; }
    public string DetailsOfAppointment { get; set; }
    public bool Assigned { get; set; }

    public VolunteerCeremonyVM()
    {
        this.AppointmentId = AppointmentId;
        this.DetailsOfAppointment = DetailsOfAppointment;
        this.Assigned = Assigned;
    }

}

Answer 1

Based on further clarification, you will want to update your ViewModel to include a VolunteerId . So it should look something like:

public class VolunteerCeremonyVM
{
    public int AppointmentId { get; set; }
    public string DetailsOfAppointment { get; set; }
    public bool Assigned { get; set; }
    public int VolunteerId { get; set; }
}

Notice that I removed the default constructor as it wasn't doing anything. When you construct the object you can use code like the following:

var model = new VolunteerCeremonyVM {
    AppointmentId = 10,
    VolunteerId = 50,
    //etc
};

As this will set all of the properties after the basic object is constructed.

Then, you will want to pass this view model into the view that is generating your action links like so: return View(model); in whatever controller action you're using.

Inside the view, you will make use of this new information. Specifically, the Html.ActionLink method requires that any extra parameters are passed to it in a route dictionary. It uses this route dictionary to build the URL that is generated for the anchor tag. You can call Html.ActionLink with an anonymous object for its fourth parameter to specify the route dictionary. The id will be the name of the parameter and Model.VolunteerId will be the value of the current volunteer.

Change the Html.ActionLink call to the following to pass an id:

@Html.ActionLink("Join Ceremony",
    "VolunteerCeremony",
    "Volunteers",
    new { id = Model.VolunteerId },
    null)

This should fill in the id parameter of the ActionLink with the currently logged in user's userId which should generate the following link: /Volunteers/VolunteerCeremony/3 or whatever the ID actually is.

For the form side, you will also need a hidden field on the form so the correct id is sent along with the request. You will need to add a VolunteerId to the form ViewModel that you create when generating the form page. Once you've done that, inside the form itself, you will need to add the following:

Html.Hidden("id", Model.VolunteerId)

This creates an <input type="hidden" name="id" value="3" /> tag that will be sent with the form on post back to the server. Since the tag's name is id this will match with the id that's defined in your controller action.