Dropdownlist post in ASP.NET MVC3 and Entity Framework Model
- by Josh Blade
I have 3 tables:
RateProfile
RateProfileID
ProfileName
Rate
RateID
RateProfileID
PanelID
Other stuff to update
Panel
PanelID
PanelName
I have models for each of these. I have an edit page using the RateProfile model. I display the information for RateProfile and also all of the Rates associated with it. This works fine and I can update it fine. However, I also added a dropdown so that I can filter Rates by PanelID. I need it to post back on change so that it can display the filtered rates.
I'm using
@Html.DropDownList("PanelID", (SelectList)ViewData["PanelDropDown"], new { onchange = "$('#RateForm').submit()" })
for my dropdownlist. Whenever it posts back to my HttpPost Edit method though, it seems to be missing all information about the Rates navigation property. It's weird because I thought it would do exactly what the input/submit button that I have in the form does (which actually passes the entire model back to my HttpPost Edit action and does what I want it to do). The panelID is properly being passed to my HttpPost Edit method and on to the next view, but when I try to query the Model.Rates navigation property is null (only when the post comes from the dropdown. Everything works fine when the post comes from my submit input).
Get Edit:
public ActionResult Edit(int id, int panelID = 1)
{
RateProfile rateprofile = db.RateProfiles.Single(r => r.RateProfileID == id);
var panels = db.Panels;
ViewData["PanelDropDown"] = new SelectList(panels, "PanelID", "PanelName", panelID);
ViewBag.PanelID = panelID;
return View(rateprofile);
}
HttpPost Edit:
[HttpPost]
public ActionResult Edit(RateProfile rateprofile, int panelID)
{
var panels = db.Panels;
ViewData["PanelDropDown"] = new SelectList(panels, "PanelID", "PanelName", panelID);
ViewBag.PanelID = panelID;
if (ModelState.IsValid)
{
db.Entry(rateprofile).State = EntityState.Modified;
foreach (Rate dimerate in rateprofile.Rates)
{
db.Entry(dimerate).State = EntityState.Modified;
}
db.SaveChanges();
return View(rateprofile);
}
return View(rateprofile);
}
View:
@model PDR.Models.RateProfile
@using (Html.BeginForm(null,null,FormMethod.Post, new {id="RateForm"}))
{
<div>
@Html.Label("Panel")
@Html.DropDownList("PanelID", (SelectList)ViewData["PanelDropDown"], new { onchange = "$('#RateForm').submit()" })
</div>
@{var rates= Model.Rates.Where(a => a.PanelID == ViewBag.PanelID).OrderBy(a => a.minCount).ToList();}
@for (int i = 0; i < rates.Count; i++)
{
<tr>
<td>
@Html.HiddenFor(modelItem => rates[i].RateProfileID)
@Html.HiddenFor(modelItem => rates[i].RateID)
@Html.HiddenFor(modelItem => rates[i].PanelID)
@Html.EditorFor(modelItem => rates[i].minCount)
@Html.ValidationMessageFor(model => rates[i].minCount)
</td>
<td>
@Html.EditorFor(modelItem => rates[i].maxCount)
@Html.ValidationMessageFor(model => rates[i].maxCount)
</td>
<td>
@Html.EditorFor(modelItem => rates[i].Amount)
@Html.ValidationMessageFor(model => rates[i].Amount)
</td>
</tr>
}
<input type="submit" value="Save" />
}
To summarize my problem, the below query in my view only works when the post comes from the submit button and not when it comes from my dropdownlist.
@{var rates= Model.Rates.Where(a => a.PanelID == ViewBag.PanelID).OrderBy(a => a.minCount).ToList();}
