Tag Archives: Programming .Net

Return simple string on ASP.NET MVC

Today I teach some of my junior programmer on how to work with ASP.NET MVC, first question they ask once they see the sample of MVC from standard Visual Studio 2010 template is “what if I want only return Hello World as the output?”, coincidently this question is the same question always being asked to me by MVC newbie.

MVC concept segregates layer of development into Model, View and Controller. Most of time developer effort will be on Controller and View and these 2 layers have a mutual relationship, because Controller will handle all business logic and/or data processing while View is meant for UI handling purpose. Sometime as programmer, we will need to test our business logic function has proper output or not, and the output normally just simple object or value. Build a different view to render the output seems too many effort to do and will add more “to-be-deleted” file on our solution, hence question on how to send simple output directly from Controller is really logical.

Okay, back to the issue, what is the solution? ASP.NET MVC have a class “ContentResult” to accomodate this problem. Code should be like below:

 

   1:  public class HomeController : Controller
   2:      {
   3:          public ActionResult Index()
   4:          {
   5:              String ret = "Hello World!";
   6:   
   7:              //-- build return string here
   8:              return Content(ret);
   9:          }
  10:     }

Have a nice MVC Controller test !!!

How to create a method returns new LINQ Join on .Net

I am in situation where I need to join 2 big tables often, doing such on physical database will consume tons of CPU resources and roundtrip overhead between business logic and data layer may kill my application performance. Hence I am thinking to  load tables into memory for first time only, use a LINQ Join and encapsulate this LINQ join query into a method and return the output as a reusable object. But I get an issue because of data returned by LINQ Join known as IEnumerable<Anonymous> and .NET need to have a valid cast before we can use the data.

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