MrBliz MrBliz - 23 days ago 5
C# Question

The parameter conversion from type 'System.String' to type ''X' failed because no type converter can convert between these types

I'm stumped with this one and your help would be most appreicated.

I get the error:


The parameter conversion from type 'System.String' to type
'DataPortal.Models.EntityClasses.FeedbackComment' failed because no
type converter can convert between these types


The
ModelState.IsValid
is failing on the
FeedbackComment.Comment
property

Any ideas?

public class FeedbackComment : IFeedbackComment
{
[Key]
public int Id { get; set;}

public int FeedbackId { get; set; }

[Required(ErrorMessage = "Please enter a Comment")]
public string Comment { get; set; }

public DateTime CommentDate { get; set; }

public string CommentBy { get; set; }
}


Controller Methods

//
// GET: /FeedbackComment/Create

public virtual ActionResult Create(int feedbackId)
{
var comment = new FeedbackComment {FeedbackId = feedbackId, CommentBy = User.Identity.Name, CommentDate = DateTime.Now};
return View(comment);
}

//
// POST: /FeedbackComment/Create

[HttpPost]
public virtual ActionResult Create(FeedbackComment comment)
{

if (ModelState.IsValid)
{

_feedbackCommentRepository.Add(comment);

return RedirectToAction(MVC.Feedback.Details(comment.FeedbackId));
}

return View(comment);
}


And the view

@model DataPortal.Models.EntityClasses.FeedbackComment
@{
ViewBag.Title = "Create Comment";
}
<h2>Create Comment</h2>






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

<div class="editor-label">
@Html.LabelFor(model => model.Comment)
</div>
<div class="editor-field">
@Html.TextAreaFor(model => model.Comment, new{@class = "TextEditor"})
@Html.ValidationMessageFor(model => model.Comment)
</div>


@Html.HiddenFor(model=> model.CommentDate)
@Html.HiddenFor(model=> model.CommentBy)
@Html.HiddenFor(model=> model.FeedbackId)

<p>
<input type="submit" value="Create" />
</p>
</fieldset>
}

<div>
@Html.ActionLink("Back to Comment Details", MVC.Feedback.Details(Model.FeedbackId))
</div>

Answer

The problem is the name of your action parameter:

public virtual ActionResult Create(FeedbackComment comment)

It's called comment. But your FeedbackComment also has a property called Comment of type string. So the default model binder gets crazy. Just rename one of the two to avoid the conflict.

For example the following will fix your issue:

public virtual ActionResult Create(FeedbackComment model)
{
    if (ModelState.IsValid)
    {
        _feedbackCommentRepository.Add(model);
        return RedirectToAction(MVC.Feedback.Details(model.FeedbackId));
    }
    return View(model);
}