I saw a similar question here on SO but I believe mine differs a little a bit.
OK, so I have a simple view here:
开发者_JAVA技巧<%@ Page Title="" Language="C#" MasterPageFile="~/Views/Shared/Site.Master" Inherits="System.Web.Mvc.ViewPage<RootFinder.Models.QuadCalc>" %>
<asp:Content ID="Content1" ContentPlaceHolderID="TitleContent" runat="server">
Polynomial Root Finder - Quadratic
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server">
<h2>Quadratic</h2>
<%= Html.BeginForm("Quadratic", "Calculate") %>
<% { %>
<div>
a: <%= Html.TextBox("quadAValue", Model.quadraticAValue) %>
<br />
b: <%= Html.TextBox("quadBValue", Model.quadraticBValue) %>
<br />
c: <%= Html.TextBox("quadCValue", Model.quadraticCValue) %>
<br />
<input type="submit" id="quadraticSubmitButton" value="Calculate!" />
<br />
<p><%= Model.x1 %></p>
<p><%= Model.x2 %></p>
</div>
<% } %>
</asp:Content>
And my controller here:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using RootFinder.Models;
namespace RootFinder.Controllers
{
public class CalculateController : Controller
{
//
// GET: /Calculate/
public ActionResult Index()
{
return View();
}
[AcceptVerbs(HttpVerbs.Get)]
public ViewResult Quadratic()
{
return View();
}
[AcceptVerbs(HttpVerbs.Post)]
public ViewResult Quadratic(QuadCalc newQuadCalc)
{
return View(newQuadCalc);
}
public ActionResult Cubic()
{
return View();
}
public ActionResult Quartic()
{
return View();
}
}
}
Now, upon loading my Get
version of the Quadratic
view, I get the following message from VS2010:
Object reference not set to an instance of an object
Now, I kind of understand the message in it of itself, but isn't it a bad thing to create a new object of a class within the View itself? Which is why I was trying to handle this in the Controller for the Post
only.....
Hmm...
Same as you do in your Post action, but in the Get you pass a new fresh initialized QuadCalc model to the view
[AcceptVerbs(HttpVerbs.Get)]
public ViewResult Quadratic() {
return View( new QuadCalc() );
}
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