Asp.net MVC 3实例学习之ExtShop（四）——完成产品列表页

在完成产品列表页前要做一些准备功夫。首先是去下载MvcPager用了为产品列表分页。下载的可能是基于MVC 2的，没关系，可以用在MVC 3上。如果有担心，下载源代码重新编译一次好了。下载后将DLL添加到引用里。

接着是要修改一下路由以实现“Catalog/List/[id]/[page]”的访问。打开“Global.asax.cs”文件，然后在默认路由之前添加以下代码：

1	routes . MapRoute (
2	" Catalog " , // Route name
3	" Catalog/List/{id}/{page} " , // URL with parameters
4	new { controller = " Catalog " , action = " List " , page = 1 } // Parameter defaults
5	) ;
6

现在打开CatalogController.cs文件，在文件头添加对MvcPager的引用，代码如下：

1	using Webdiyer . WebControls . Mvc;

然后修改Index操作的代码如下：

1	public ActionResult Index ( int? id )
2	{
3	PagedList < T_Products > q = dc . T_Products . OrderByDescending ( m = > m . CreateTime ) . ToPagedList ( id ?? 1 , 8 ) ;
4	return View ( q ) ;
5	}
6

代码传入的id是页码而不是产品分类编码，这个要注意。因为要使用分页，所以传递给视图的是PagedList对象，而不是Queryable，这也是要注意的地方。因而，查询结果需要通过toPagedList方法将Queryable对象转换为PagedList对象。第1个参数是当前页面，如果id为空，则默认为第1页。第2个参数是每页显示的产品数量，在这里是8个。

在“Index”上单击鼠标右键，选择“添加视图”（

，今天换了中文版，菜单也变了）。在视图中添加以下代码：

1	@ using Webdiyer . WebControls . Mvc ;
2	@ model PagedList < Extshop . Models . T_Products >
3
4	@ {
5	ViewBag . Title = " 产品列表 " ;
6	PageData [ " id " ] = " " ;
7	}
8	< div class = " nav " >
9	< a href = " @Url.Action( " " , " Catalog " ) " > 产品 < / a >
10	< / div > < br / >
11	< div id = " contentMain " style = " width:760px; " >
12	< span class = " header " style = " width:750px; " > 产品列表 < / span >
13	@ {
14	foreach ( var c in Model )
15	{
16	< ul >
17	< li > < a href = ' @ Url . Action ( " Details " , " Product " , new { id = c . ProductID } ) ' > < img src = ' / Images / products/ @ c . SamllImageUrl ' alt = " @c.Title " / > < / a > < / li >
18	< li class = ' title ' > < a href = ' @ Url .Action ( " Details " , " Product " , new { id = c . ProductID } ) ' > @ c . Title< / a > < / li >
19	< li > 市场价： < del > @ c . MarketPrice . ToString ( "C " ) < / del > < / li >
20	< li > 当前价： @ c . UnitPrice . ToString ( " C " ) < /li >
21	< li > < span class = " rating-title " > 评 价： < /span >
22	< div class = ' rating ' id = "@c.ProductID.ToString( " rat - 0 " ) " >
23	< input name = "@c.ProductID.ToString( " Star0 " ) " type = " radio " class = " star " disabled = "disabled " value = " 1 " @ ( c . TotalRating = = 1 ? " checked='checked' " : "" ) / >
24	< input name = "@c.ProductID.ToString( " Star0 " ) " type = " radio " class = " star " disabled = "disabled " value = " 2 " @ ( c . TotalRating = = 2 ? " checked='checked' " : "" ) / >
25	< input name = "@c.ProductID.ToString( " Star0 " ) " type = " radio " class = " star " disabled = "disabled " value = " 3 " @ ( c . TotalRating = = 3 ? " checked='checked' " : "" ) / >
26	< input name = "@c.ProductID.ToString( " Star0 " ) " type = " radio " class = " star " disabled = "disabled " value = " 4 " @ ( c . TotalRating = = 4 ? " checked='checked' " : "" ) / >
27	< input name = "@c.ProductID.ToString( " Star0 " ) " type = " radio " class = " star " disabled = "disabled " value = " 5 " @ ( c . TotalRating = = 5 ? " checked='checked' " : "" ) / >
28	< / div >
29	< / li >
30	< / ul >
31	}
32	}
33	< div class = " clear " > < / div >
34	< div class = ' pagenav ' > @ Html . Pager ( Model , new PagerOptions { PageIndexParameterName = " id " } ) < / div >
35	< / div >
36
37	< script type = " text/javascript " >
38	jQuery ( function ( ) {
39	$ ( " div .rating " ) . stars ( ) ;
40	} ) ;
41	< / script >
42

代码第一句引用MvcPager，第二句定义接收的数据模型类型。因为是所以产品列表，所以PageData["id"]设置为空字符串。其余代码和首页的差不多。第34句使用HTML方式显示分页代码。这里要注意的是PagerOptions选项中的PageIndexParameterName要设置为id，因为操作中接收的当前页参数是以id定义的。

页面需要正常显示，还需要在Site.css中添加以下代码：

1	#contentMain .clear { clear : both ; }
2	#contentMain .pagenav { width : 760px ; text-align : center ; margin-bottom : 10px ; }

切换回CatalogController.cs文件，在Index操作下添加一个List操作，其代码如下：

1	public ActionResult List(string id, int? page)
2	{
3	ViewData["id"] = id;
4	PagedList q = dc.T_Products
5	.Where(m => dc.T_Categories.Where(n => n.CategoryID.Substring(0, id.Length) == id).Select(n => n.CategoryID ).Contains(m.CategoryID))
6	.OrderByDescending(m => m.CreateTime).ToPagedList(page ?? 1, 4);
7	return View(q);
8	}
9

从代码可以看到，List操作有两个参数，第1个是分类id，第2个是当前页号。第3行通过ViewData["id"]向视图传递当前的分类id，以更新左边分类列表以及显示导航条。其余的和Index操作差不多。现在为List操作创建一个视图，视图内代码如下：

1	@ using Webdiyer . WebControls . Mvc ;
2	@ model PagedList < Extshop . Models . T_Products >
3	@ {
4	ViewBag . Title = " 产品列表 " ;
5	PageData [ " id " ] = ViewData [ " id " ] ;
6	}
7
8	< div class = " nav " >
9	< a href = " @Url.Action( " " , " Catalog " ) " > 产品 < / a >
10	@ { Html . RenderAction ( " Navbar " , " Catalog " , new { id = ViewData [ " id " ] } ) ; }
11	< / div > < br / >
12	< div id = " contentMain " style = " width:760px; " >
13	< span class = " header " style = " width:750px; " > 产品列表 < / span >
14	@ {
15	foreach ( var c in Model )
16	{
17	< ul >
18	< li > < a href = ' @ Url . Action ( " Details " , " Product " , new { id = c . ProductID } ) ' > < img src = ' / Images / products/ @ c . SamllImageUrl ' alt = " @c.Title " / > < / a > < / li >
19	< li class = ' title ' > < a href = ' @ Url .Action ( " Details " , " Product " , new { id = c . ProductID } ) ' > @ c .Title < / a > < / li >
20	< li > 市场价： < del > @ c . MarketPrice . ToString (" C " ) < / del > < / li >
21	< li > 当前价： @ c . UnitPrice . ToString ( " C " ) </ li >
22	< li > < span class = " rating-title " > 评 价： < /span >
23	< div class = ' rating ' id = "@c.ProductID.ToString( " rat - 0 " ) " >
24	< input name = "@c.ProductID.ToString( " Star0 " ) " type = " radio " class = " star " disabled = "disabled " value = " 1 " @ ( c . TotalRating = = 1 ? " checked='checked' " : "" ) / >
25	< input name = "@c.ProductID.ToString( " Star0 " ) " type = " radio " class = " star " disabled = "disabled " value = " 2 " @ ( c . TotalRating = = 2 ? " checked='checked' " : "" ) / >
26	< input name = "@c.ProductID.ToString( " Star0 " ) " type = " radio " class = " star " disabled = "disabled " value = " 3 " @ ( c . TotalRating = = 3 ? " checked='checked' " : "" ) / >
27	< input name = "@c.ProductID.ToString( " Star0 " ) " type = " radio " class = " star " disabled = "disabled " value = " 4 " @ ( c . TotalRating = = 4 ? " checked='checked' " : "" ) / >
28	< input name = "@c.ProductID.ToString( " Star0 " ) " type = " radio " class = " star " disabled = "disabled " value = " 5 " @ ( c . TotalRating = = 5 ? " checked='checked' " : "" ) / >
29	< / div >
30	< / li >
31	< / ul >
32	}
33	}
34	< div class = " clear " > < / div >
35	< div class = ' pagenav ' > @ Html . Pager ( Model , new PagerOptions { PageIndexParameterName = " page " } ) < / div >
36	< / div >
37
38	< script type = " text/javascript " >
39	jQuery ( function ( ) {
40	$ ( " div .rating " ) . stars ( ) ;
41	} ) ;
42	< / script >
43
44
45

代码第10行通过一个分部视图显示导航菜单。第35行要注意PageIndexParameterName是“page”，而不是Index视图的“id”了。

下一步要做的是完成导航条的显示。将文件切换回CatalogController.cs文件，添加一个名称为“Navbar”的子操作，其代码如下：

1	[ ChildActionOnly ]
2	public ActionResult Navbar ( string id )
3	{
4	List < string > idlist = new List < string > ( ) ;
5	idlist . Add ( id ) ;
6	for ( int i = 0 ; i < ( id . Length - 2 ) ; i = i + 3 )
7	{
8	idlist . Add ( id . Substring ( 0 , i + 3 ) ) ;
9	}
10	var q = dc . T_Categories . Where ( m = > idlist . Contains ( m. CategoryID ) ) . OrderBy ( m = > m . CategoryID ) ;
11	return PartialView ( q ) ;
12	}
13

代码首先获取了当前分类的父类编号，然后从数据库一次查询出所有类别并排序。现在为该子操作创建一个分部视图，视图代码如下：

1	@ model IEnumerable < Extshop . Models . T_Categories >
2
3	@ {
4	foreach ( var c in Model )
5	{
6	@ Html . Raw ( " >> " ) < a href = ' @ Url . Action ( " List " , " Catalog " , new { id = c . CategoryID } ) ' > @ c . Titel < / a >
7	}
8	}

代码中，“>>”的显示必须用Html的Raw方法显示，不然会提示错误，使用“>”也不行，估计是和Razor的语法有冲突。是否有其它办法，没去研究了。

至此，产品列表页的就已经完成了。

BTW：因为项目还没完成，所以没考虑提供源代码，但有读者希望在看文章的同时能提供源代码做参考，所以从本文开始，每完成一节，就提供到该节的代码。

源代码：http://download.csdn.net/source/2996287