DotNetDrop

Table value parameters with Enterprise Library Data Access Application Block

admin — Tue, 03 Nov 2009 18:59:17 +0000

I wasn’t finding much with a quick search for enterprise library table value parameters or data access application block table value parameters. After a bit of research I discovered that versions <= 4.1 don't support tvps as well as I'd hoped. The key is you must cast (or create) a SqlDatabase and use SqlDbType.Structured. This will break your database independent code. The easiest way I see to use table parameters is create a DataTable and add columns to match the parameter. The column names of this table do not matter.

            DataTable table = new DataTable();
            table.Columns.Add(new DataColumn("ID", typeof(int)));
            table.Columns.Add(new DataColumn("Value", typeof(int)));
            table.Rows.Add(new object[] { ID, value });
 
            SqlDatabase database = (SqlDatabase)DatabaseFactory.CreateDatabase("DatabaseName");
            DbCommand dbCommand = database.GetStoredProcCommand("[StoredProcName]");
            database.AddInParameter(dbCommand, "@MyTableValueParameter", SqlDbType.Structured, table);
            using (IDataReader reader = database.ExecuteReader(dbCommand))
            ...

WPF/Silverlight named color chart table thingie

admin — Wed, 08 Apr 2009 19:51:25 +0000

I ran across a color chart for the named colors the other day while searching for something wpf related. It took me too long to find it today. The next time I’m digging around in my xaml for a background color and see BlanchedAlmond I’ll have a reference.

Wpf Silverlight System Color Chart Table

from:

http://msdn.microsoft.com/en-us/library/system.windows.media.solidcolorbrush.color(VS.95).aspx

Json serialization of PaginatedList does not include list properties

admin — Sun, 05 Apr 2009 05:30:13 +0000

Lately I’ve been playing around with Asp.Net Mvc. I’m trying to adapt the NerdDinner sample for a project I’m working on. The sample includes a class called PaginatedList. PaginatedList looks something like this:

   public class PaginatedList<T> : List<T>
   {
        public int PageIndex  { get; private set; }
        public int PageSize   { get; private set; }
        public int TotalCount { get; private set; }
        public int TotalPages { get; private set; }
   }

My controller method looks something like this:

   public ActionResult FindBusinessesByName(string businessName, int limit, int page)
   {
      BusinessRepository repository = new BusinessRepository();
      PaginatedList<Business> paginatedBusinesses = new PaginatedList<Business>(repository.FindBusinessesByName(businessName), page, limit);
      return Json(paginatedBusinesses);
   }

I’m using jQuery to get a PaginatedList of businesses from my controller. I use the list of businesses to create an unordered list to display the business information. I haven’t played with jQuery or json serialization much so I was surprised to see that only the business data was returned. The extra properties on the PaginatedList were not. I dug around a bit and downloaded the newly released source for Mvc (woot!). I found the two lines in JsonResult.cs that do the serialization:

                JavaScriptSerializer serializer = new JavaScriptSerializer();
                response.Write(serializer.Serialize(Data));

A quick search for JavaScriptSerializer shows that List becomes an “Array that uses JSON array syntax”. So it appears that since PaginatedList derives from List the serializer ignores the properties on the PaginatedList.

I was able to work around this by changing my controller method to this:

        public ActionResult FindBusinessesByName(string businessName, int limit, int page)
        {
            BusinessRepository repository = new BusinessRepository();
            PaginatedList<Business> paginatedBusinesses = new PaginatedList<Business>(repository.FindBusinessesByName(businessName), page, limit);
            var paginationContainer = new
            {
                PageIndex = paginatedBusinesses.PageIndex,
                PageSize = paginatedBusinesses.PageSize,
                TotalCount = paginatedBusinesses.TotalCount,
                TotalPages = paginatedBusinesses.TotalPages,
                Businesses = paginatedBusinesses
            };
            return Json(paginationContainer);
        }

Error generating MVC view for Entity Framework model

admin — Sat, 04 Apr 2009 22:22:15 +0000

I’m trying to generate a view for Asp.Net MVC 1.0 using an Entity Framework model. This is from Details.tt. Anyone seen this error?

I get this the first time I try to generate:

error CS0234: Compiling transformation: The type or namespace name ‘Data’ does not exist in the namespace ‘System’ (are you missing an assembly reference?)

And if I try to generate again:

—————————
Template Processing resulted in 2 Errors
—————————
C:\Program Files\Microsoft Visual Studio 9.0\Common7\IDE\ItemTemplates\CSharp\Web\MVC\CodeTemplates\AddView\Details.tt(-1,-1) : error : The host threw an exception while trying to resolve the assembly reference ‘System.Data.Entity’. The transformation will not be run. The following Exception was thrown:

System.ArgumentOutOfRangeException: Length cannot be less than zero.

Parameter name: length

at System.Reflection.Assembly._nLoad(AssemblyName fileName, String codeBase, Evidence assemblySecurity, Assembly locationHint, StackCrawlMark& stackMark, Boolean throwOnFileNotFound, Boolean forIntrospection)

at System.Reflection.Assembly.nLoad(AssemblyName fileName, String codeBase, Evidence assemblySecurity, Assembly locationHint, StackCrawlMark& stackMark, Boolean throwOnFileNotFound, Boolean forIntrospection)

at System.Reflection.Assembly.InternalLoad(AssemblyName assemblyRef, Evidence assemblySecurity, StackCrawlMark& stackMark, Boolean forIntrospection)

at System.Reflection.Assembly.InternalLoad(String assemblyString, Evidence assemblySecurity, StackCrawlMark& stackMark, Boolean forIntrospection)

at System.Reflection.Assembly.Load(String assemblyString)

at Microsoft.VisualStudio.Web.Mvc.MvcTextTemplateHost.Microsoft.VisualStudio.TextTemplating.ITextTemplatingEngineHost.ResolveAssemblyReference(String assemblyReference)

at Microsoft.VisualStudio.TextTemplating.Engine.CompileAndRunCode(String generatorCode, ITextTemplatingEngineHost host, TemplateProcessingSession session)