Question

NOTE: Edited to add the Model

The Problem: a querystring guid value is giving me fits, trying to get it into my controller so I can Create a new record with it as a parameter. The closest that I’ve gotten so far loads a record with all 0’s and dashes for the guid (which is not only wrong but looks very weird.)

This is in MVC3/EF4 with a legacy database and some legacy pages and URLs. The application that I’m working on includes a note-taking functionality, where User A can makes notes about User B (for example.) Both users have their own guid Ids that identify them, and the table where the notes are stored has an Id column for the note itself and then two Id columns to keep track of which is User A and which is User B for this particular note.

We can always assume that User A is the current User, and get his Id that way. One of the legacy URLs is how you get the Id for User B.

For example: http://www.mysite.com/notes/user/ED88B0B1-B552-4D63-BD20-C94B837440BE

“User A” in our example has the guid of ScannerUserId

“User B” (from the querystring) has the guid of ScannedCodeId

Here is the model:

public partial class Note
{
    public System.Guid ScannerUserId { get; set; }
    public System.Guid ScannedCodeId { get; set; }
    public System.Guid NoteId { get; set; }
    public string NoteDetail { get; set; }

    public virtual Code Code { get; set; }
    public virtual Contact Contact { get; set; }
}

Here is the view:

@model MySite.Models.Note

@{
ViewBag.Title = "Create";
}

<h2>Create</h2>

<script src="@Url.Content("~/Scripts/jquery.validate.min.js")" type="text/javascript"></script>
<script src="@Url.Content("~/Scripts/jquery.validate.unobtrusive.min.js")" type="text/javascript"></script>

@using (Html.BeginForm()) {
@Html.ValidationSummary(true)
<fieldset>
    <legend>Note</legend>

    <div class="editor-label">
        @Html.LabelFor(model => model.NoteDetail)
    </div>
    <div class="editor-field">
        @Html.EditorFor(model => model.NoteDetail)
        @Html.ValidationMessageFor(model => model.NoteDetail)
    </div>
    <p>
        <input type="submit" value="Create" />
    </p>
</fieldset>
}

And here is the controller section on Create:

public class NoteController : Controller
{
    //
    // GET: /Note/Create

    public ActionResult Create()
    {
        ViewBag.ScannedCodeId = new SelectList(db.Codes, "CodeId", "ScannedCodeId");
        ViewBag.ScannerUserId = new SelectList(db.Contacts, "UserId", "ScannerUserId");
        return View();
    } 
    //
    // POST: /Note/Create

    [HttpPost]
    public ActionResult Create(Note note)
    {
        if (ModelState.IsValid)
        {
            note.NoteId = Guid.NewGuid();
            note.ScannerUserId = (Guid)System.Web.Security.Membership.GetUser().ProviderUserKey;
            //note.ScannedCodeId = new Guid(Request.QueryString[""]);
            note.CreateDate = DateTime.Now;
            note.LastActivityDate = DateTime.Now;
            db.Notes.Add(note);
            db.SaveChanges();
            return RedirectToAction("Index");  
        }

        ViewBag.ScannedCodeId = new SelectList(db.Codes, "CodeId", "ScannedCodeId", note.ScannedCodeId);
        ViewBag.ScannerUserId = new SelectList(db.Contacts, "UserId", "ScannerUserId", note.ScannerUserId);
        return View(note);
    }

How do I get the guid that is in the querystring into the note.ScannedCodeId such that the db.SaveChanges will not blow up on me?

And also, thank you for reading this far and anything you can do to help.

Answer 1

I believe Note is your ViewModel.Add a WrittenFor property to that

(I am using Int datatype in this example to keep this answer simple and much readable. you can replace it with the string for your unique id/guid)

public class Note
{
  public string NoteDescr { set;get;}
  public int WrittenBy { set;get;}
  public int WrittenFor { set;get;}

}

and in your get action method return this view model to your view

[HttpGet]
public ActionResult Create(int friendId)
    {
        Note objVm=new Note();
        objVm.WrittenFor=friendId;
        return View(objVm);
    } 

So the user can access this page by browsing like

http://yourdomain/yourcontroller/create/589476

That means you (The current use is in the wall (or note book..:) ) of user with id 589476.

and in your View, Have it in the form using @Html.HiddenFor HTml helper method. Then when you submit your form, you will get it in your viewmode which is a parameter of your HttpPost Create method

@model Note

@using (Html.BeginForm())
{   
  @Html.TextBoxFor(m=>m.NotDesc)
  @Html.HiddenFor(m => m.WrittenFor)
  <input type="submit" value="Create" />
}

and in your HttpPost action method, you have what you want

[HttpGet]
public ActionResult Create(Note objNote)
{
   int friendId= objNote.WrittenFor 
   string note=objNote.NoteDesc
   //Now you can save your value 
}