Dear All,
I am curious on how does EF work.
I have the following code. I want it to
1) display my category in the home page.
2) And when user chosen a category, it should display the sub category.
3) And when sub category chosen, it should display the list of books in that sub category.
Problem encountered:
I am able to get to step 2. So, following the same idea, i created a method, 'BookPDF', hoping to to display the list of books. However, this is not successful.
From the URL,
http://localhost:1090/Home/BookPDF?subid=1002
I can tell that the subid is passed from previous view (SubCategory) but no book title displayed.
Please find the print screen for the steps that i had gone through and the database query result in the attachment. This is to show that i have data populated, but the EF refused? to pick up the book title.
Can someone please help me with my problem?
[code]
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using MVCLibrary.Models;
namespace MVCLibrary.Controllers
{
public class HomeController : Controller
{
FYP_OPL_FileStreamEntities db = new FYP_OPL_FileStreamEntities();
public ActionResult Index()
{
//return View();
var categories = db.Categories.ToList();
return View(categories);
}
public ActionResult SubCategory(int? s_catid)
{
if (s_catid != null)
{
var subcategories = db.Categories.Include("Sub_Categories").Single(s => s.C_Catid == s_catid);
return View(subcategories);
}
else
return View();
}
public ActionResult BookPDF(int? s_subId)
{
if (s_subId != null)
{
var bookdetails = db.BookDetails.Include("BookPDF").Single(b => b.B_SubId == s_subId);
return View(bookdetails);
}
else
//return RedirectToAction("SubCategory");
return View();
}
[/code]
and my Index
[code]
@model IEnumerable<MVCLibrary.Models.Category>
@{
ViewBag.Title = "Home Page";
}
<ul>
@foreach (var Categories in Model)
{
<li>@Html.ActionLink(Categories.C_Description, "SubCategory", new { s_catid = Categories.C_Catid })</li>
}
</ul>
[/code]
and my SubCategory
[code]
@model MVCLibrary.Models.Category
@{
ViewBag.Title = "SubCategory";
}
<h2>Browsing SubCategory</h2>
<ul>
@foreach (var subcategory in Model.Sub_Categories)
{
<li>
@Html.ActionLink(subcategory.S_Description, "BookPDF", new { subid = subcategory.S_SubId })
</li>
}
</ul>
[/code]
and my BookPDF
[code]
@model IEnumerable<MVCLibrary.Models.BookDetail>
@{
ViewBag.Title = "BookPDF";
}
<h2>BookPDF</h2>
@if(Model != null )
{
<ul>
@foreach (var books in Model)
{
<li>@Html.ActionLink(books.B_Title, "BookPDF", new { B_ISBN = books.B_ISBN })</li>
}
</ul>
}
<div>Record not found</div>
[/code]