Object Reference not set to an object (calling Raz

问题:

This question already has an answer here:

• What is a NullReferenceException, and how do I fix it? 31 answers

Using C# MVC4

My View:

@using Universe.Models
@model UserModel
@section css {
<link href="@Url.Content("~/Content/assets/charcreation.css")" rel="stylesheet"/>}
@using (Html.BeginForm("AddUser","Home", FormMethod.Post))
{

<div class="row-fluid">
            <table id="tblBio">
                <tr>
                    <td class="span3">
                        <span class="labeltext">Alias:</span>
                    </td>
                    <td class="span5">
                        @Html.TextBox(Model.Alias)
                    </td>
                    <td class="span4">
                        <span class="ui-state-highlight hidden"></span>
                    </td>
                </tr>

My Model:

public class UserModel
{
    public int Id { get; set; }
    public string Alias { get; set; }
    public string Email { get; set; }
    public string Password { get; set; }
    public bool IsExternal { get; set; }


    public UserModel()
    {

    }

    public UserModel(User user)
    {
        if (user == null) return;
        Alias = user.Alias;
    }
}

But, I keep getting the error:

When I try to debug it, it doesn't even go into the Html.TextBox method or into my model.

回答1:

Without seeing your controller action, my guess would be that your model is null.

In your controller, make sure you are passing an instance of the model to your view. For example:

return View(new UserModel());

Instead of:

return View();

回答2:

You have to pass your Model in your Controller Action when return the specific View

return View(new Model());