ASP.NET MVC with Entity Framework and CSS一书翻译系列文章之第六章：管理产品图片：多对多关系(上)

 1 using BabyStore.Models;
 2 
 3     using System.Data.Entity;
 4 
 5    namespace BabyStore.DAL
 6 
 7   {
 8 
 9           public class StoreContext:DbContext
10 
11         {
12 
13              public DbSet<Product> Products{get;set;}
14 
15             public DbSet<Category> Categories{get;set;}
16 
17             public DbSet<ProductImage> ProductImages{get;set;}
18 
19         }
20 
21   }

 1 namespace BabyStore
 2 
 3 {
 4 
 5     public static class Constants
 6 
 7    {
 8 
 9        public const string ProductImagePath="~/Content/ProductImages/"; 
10 
11        public const string ProductThumbnailPath="~/Content/ProductImages/Thumbnails/";
12 
13    }
14 
15 }

 1 public ActionResult Index(string category, string search, string sortBy, int? page)
 2 {
 3 //instantiate a new view model
 4 ProductIndexViewModel viewModel = new ProductIndexViewModel();
 5 //select the products
 6 var products = db.Products.Include(p => p.Category);
 7 //perform the search and save the search string to the viewModel
 8 if (!String.IsNullOrEmpty(search))
 9 {
10 products = products.Where(p => p.Name.Contains(search) ||
11 p.Description.Contains(search) ||
12 p.Category.Name.Contains(search));
13 viewModel.Search = search;
14 }
15 //group search results into categories and count how many items in each category
16 viewModel.CatsWithCount = from matchingProducts in products
17 where
18 matchingProducts.CategoryID != null
19 group matchingProducts by
20 matchingProducts.Category.Name into
21 catGroup
22 select new CategoryWithCount()
23 {
24 CategoryName = catGroup.Key,
25 ProductCount = catGroup.Count()
26 };
27 if (!String.IsNullOrEmpty(category))
28 {
29 products = products.Where(p => p.Category.Name == category);
30 viewModel.Category = category;
31 }
32 //sort the results
33 switch (sortBy)
34 {
35 case "price_lowest":
36 products = products.OrderBy(p => p.Price);
37 break;
38 case "price_highest":
39 products = products.OrderByDescending(p => p.Price);
40 break;
41 default:
42 products = products.OrderBy(p => p.Name);
43 break;
44 }
45 int currentPage = (page ?? 1);
46 viewModel.Products = products.ToPagedList(currentPage, Constants.PageItems );
47 viewModel.SortBy = sortBy;
48 viewModel.Sorts = new Dictionary<string, string>
49 {
50 {"Price low to high", "price_lowest" },
51 {"Price high to low", "price_highest" }
52 };
53 return View(viewModel);
54 }

 1 private bool ValidateFile(HttpPostedFileBase file)
 2 {
 3    string fileExtension=System.IO.Path.GetExtension(file.FileName).ToLower();
 4   string[] allowedFileTypes={".gif",".png",".Jpeg",".jpg"};
 5   if((file.ContentLength>0&&file.ContentLength<2097152)&&allowedFileType.Contains(fileExtension))
 6 {
 7       return true;
 8 }
 9 return false;
10 }

 1 private void SaveFileToDisk(HttpPostedFileBase file)
 2 {
 3      WebImage img=new WebImage(file.InputStream);
 4     if(img.Width>190)
 5    {
 6        img.Resize(190,img.height);
 7    }
 8  img.Save(Constents.ProductImagePath+file.FileName);
 9    if(img.Width>100)
10   {
11         img.Resize(100,img.Height);
12   }
13  img.Save(Constents.ProductThumbnailPath+file.FileName);
14 }

 1 [HttpPost]
 2 [ValidateAntiForgeryToken]
 3 public ActionResult Upload( HttpPostedFileBase file )
 4 {
 5 //check the user has entered a file
 6 if (file != null)
 7 {
 8 //check if the file is valid
 9 if (ValidateFile(file))
10 {
11 try
12 {
13 SaveFileToDisk(file);
14 }
15 catch (Exception)
16 {
17    ModelState.AddModelError("FileName", "Sorry an error occurred saving the file
18 to disk, please try again");
19 }
20 }
21 else
22 {
23 ModelState.AddModelError("FileName", "The file must be gif, png, jpeg or jpg and
24 less than 2MB in size");
25 }
26 }
27 else
28 {
29 //if the user has not entered a file return an error message
30 ModelState.AddModelError("FileName", "Please choose a file");
31 }
32 if (ModelState.IsValid)
33 {
34 db.ProductImages.Add( new ProductImage { FileName = file.FileName } );
35 db.SaveChanges();
36 return RedirectToAction("Index");
37 }
38 return View();
39 }

1 //check the user has entered a file
2 if (file != null)
3 {
4 }
5 else
6 {
7 //if the user has not entered a file return an error message
8 ModelState.AddModelError("FileName", "Please choose a file");
9 }

 1 //check if the file is valid
 2 if (ValidateFile(file))
 3 {
 4 try
 5 {
 6 SaveFileToDisk(file);
 7 }
 8 catch (Exception)
 9 {
10 ModelState.AddModelError("FileName", "Sorry an error occurred saving the file to disk,
11 please try again");
12 }
13 }
14 else
15 {
16 ModelState.AddModelError("FileName", "The file must be gif, png, jpeg or jpg and less than
17 2MB in size");
18 }

1 if (ModelState.IsValid)
2 {
3 db.ProductImages.Add(new ProductImage { FileName = file.FileName });
4 db.SaveChanges();
5 return RedirectToAction("Index");
6 }
7 return View();

 1 @model BabyStore.Models.ProductImage
 2 @{
 3 ViewBag.Title = " Upload Product Image ";
 4 }
 5 <h2>@ViewBag.Title</h2>
 6 @using (Html.BeginForm("Upload", "ProductImages", FormMethod.Post, new { enctype =
 7 "multipart/form-data" }))
 8 {
 9 @Html.AntiForgeryToken()
10 <div class="form-horizontal">
11 @Html.ValidationSummary(true, "", new { @class = "text-danger" })
12 <div class="form-group">
13 @Html.LabelFor(model => model.FileName, htmlAttributes: new { @class = "controllabel
14 col-md-2" })
15 <div class="col-md-10">
16 <input type="file" name="file" id="file" class="form-control"/>
17 @Html.ValidationMessageFor(model => model.FileName, "", new { @class = "textdanger"
18 })
19 </div>
20 </div>
21 <div class="form-group">
22 <div class="col-md-offset-2 col-md-10">
23 <input type="submit" value=" Upload " class="btn btn-default" />
24 </div>
25 </div>
26 </div>
27 }
28 <div>
29 @Html.ActionLink("Back to List", "Index")
30 </div>
31 @section Scripts {
32 @Scripts.Render("~/bundles/jqueryval")
33 }

1 <ul class="nav navbar-nav">
2 <li>@Html.ActionLink("Home", "Index", "Home")</li>
3 <li>@Html.ActionLink("Shop by Category", "Index", "Categories")</li>
4 <li>@Html.RouteLink("View all our Products", "ProductsIndex")</li>
5 <li>@Html.ActionLink("Manage Images", "Index", "ProductImages")</li>
6 </ul>

1 @Html.ActionLink("Create New", "Create") to @Html.ActionLink("Upload New Image", "Upload")

 1 using System.ComponentModel.DataAnnotations;
 2 using System.ComponentModel.DataAnnotations.Schema;
 3 namespace BabyStore.Models
 4 {
 5 public class ProductImage
 6 {
 7 public int ID { get; set; }
 8 [Display(Name = "File")]
 9 [StringLength(100)]
10 [Index(IsUnique = true)]
11 public string FileName { get; set; }
12 }
13 }

using System.Data.SqlClient;
using System.Data.Entity.Infrastructure;