MVC

In my second or third MVC3 project, I have really enjoyed Model Binding and my familiarity with the MVVM pattern in WPF translated well.  Web projects are much more enjoyable in c# for me than they were in the old webforms days.  Additionally, I found features in c# 4.0 that I really like, and frequently find myself taking advantage of nullable parameters, and lambda expressions.  I was asked to replicate legacy code in MVC3, which simply retrieved a feed of xml from a web service and turned them into a searchable data store of links.  Caching was a new feature of this.  The number of links was relatively small enough, that I decided to use file, not database, for the store, and simply creating my data model class with simple .net types allowed me to save my models in Properties.Settings.   In this code sample you will see the model, including a list of IEnumerable Headlines of either type of an enum, since we use this to serve up actually two different pages- InTheNews for public third party publications (WBAL, Women’s World) and NewsReleases (company generated PR)…

In the Controller, I use an abstract class because this might be served from the Desktop Web Site, or another project, for the Mobile site.  Most of the functionality is in the abstract controller, but the final  controller must implement the Save and Load functions of whatever data store they use, in our case the Properties.Settings.   Here I get to use the new Xml.Linq libraries which make loading an xml document from a url and parsing it one liners…

private Models.NewsModel GetFilteredNews(Models.NewsModel news)
        {
            Models.NewsModel allnews = GetAllNews(news.NewsType);
            news.SearchTypes = allnews.SearchTypes; // recreate dropdownlist- lost on postback?
            news.Headlines = allnews.Headlines
                .Where(h => h.NewsType == news.NewsType &&
                    (news.SearchEndDate == null || h.PostDate < news.SearchEndDate) &&
                    (news.SearchStartDate == null || h.PostDate > news.SearchStartDate) &&
                    (news.SearchType == null || news.SearchType == h.ArticleType) &&
                    (String.IsNullOrEmpty(news.SearchString) || h.Link.ToString().ToLower().Contains(news.SearchString.ToLower()))
                    ).OrderByDescending(h => h.PostDate);
 return news;
        }
private Models.NewsModel GetAllNews(Models.NewsType newstype)
        {
            Models.NewsModel news = GetSavedNews();
 if (news.LastUpdateDate < DateTime.Now.AddDays(-1))
            {
 // get feed from vocus 
                Models.Headline[] latest = GetVocusFeed();
 if (latest.Count() > 0)  // if vocus is down?
                {
                    news.Headlines = latest;
                    news.LastUpdateDate = DateTime.Now;
                    SaveNews(news);
                }
            }
 // process for the view
            news.NewsType = newstype;
            news.SearchTypes = news.Headlines.Where(h=>h.NewsType == newstype && !String.IsNullOrEmpty(h.ArticleType))
                .OrderBy(h => h.ArticleType).Distinct()
                .Select(h => new System.Web.Mvc.SelectListItem
                {
                    Text = h.ArticleType,
                    Value = h.ArticleType
                }).ToList();
 return news;
        }
private Models.Headline[] GetNewsFeed()
        {
            List<Models.Headline> headlines = new List<Models.Headline>();
            System.Xml.Linq.XDocument collateral = System.Xml.Linq.XDocument.Load(
http://somenewsfeed.com/Custom/CustomXmlFeed.aspx?something=something);
            System.Xml.Linq.XDocument news = System.Xml.Linq.XDocument.Load(
                http://somenewsfeed.com/Custom/CustomXMLFeed.aspx?somethingelse=something);
            headlines.AddRange(news.Descendants(System.Xml.Linq.XName.Get("NewsResults")).Select(e => new Models.Headline
            {
                ArticleType = GetField(e, "News_MediaOutletSortName"),
                Link = GetLink(e, "News"),
                NewsType = Models.NewsType.InTheNews,
                PostDate = DateTime.Parse(GetField(e, "News_NewsDate"))
            }).Where(e => e.Link != null));
            headlines.AddRange(collateral.Descendants(System.Xml.Linq.XName.Get("SomeResults")).Select(e => new Models.Headline
            {
                ArticleType = GetField(e, "A_Name"),
                Link = GetLink(e, "ALink"),
                NewsType = Models.NewsType.NewsReleases,
                PostDate = DateTime.Parse(GetField(e, "PublishDate"))
            }).Where(e => e.Link != null));
 return headlines.ToArray();
        }

The html page is simple enough, with clean model binding and the html helpers.  Note the handy “If” MvcHtmlString extension and the use of templating for Headlines. 

<h2 style="margin:30px;">@Html.DisplayFor(m=>m.Title)</h2>
@using (Html.BeginForm())
{
        @Html.ActionLink("Request Customized News", "RequestCustomizedNews").If(Model.NewsType == SomeBase.Models.NewsType.NewsReleases)
<div style="float:left; width:200px; display:block;">
 <h3 >Search Archives</h3>
 <div class="display-label">Headline</div>
 <div class="display-field">
                @Html.EditorFor(model => model.SearchString)
 </div>
 
 <div class="display-label">Type</div>
 <div class="display-field">
                @Html.DropDownListFor(m=>m.SearchType, Model.SearchTypes, "All")
 </div>
 <div class="display-label">From:</div>
 <div class="display-field">
                @Html.TextBoxFor(model => model.SearchStartDate, new { @class = "calendar", @Value=Model.SearchStartDate.HasValue? Model.SearchStartDate.Value.ToString(MH.Web.Mvc3.lib.CONST.DATEFORMATSTRING_SHORT): null })
 </div>
 <div class="display-label">To:</div>
 <div class="display-field">
                @Html.TextBoxFor(model => model.SearchEndDate, new { @class = "calendar" })
 </div>
 <input type="submit" value="Go" />
</div>
<div style="float:left;">
 <h3>Recent Articles</h3>
 <div>
                @Html.DisplayFor(m => m.Headlines)
 </div>
</div>
</div>
}

{Global.asax}