Archive | January, 2013

Form swapping with ASP.Net MVC 4, jQuery and Ajax

In this screen cast I will demonstrate how swap forms within in a section of your page using jQuery and AJAX.

This technique allows you to make your web sites faster and provide an easier (and better user experience).

Get the source code by clicking here.

Financial Functions in .Net (C#)

I recently worked on a project where I had to perform financial calculations. The main project requirements where provided on an Excel and because of the sensitivity of the calculations(mortgage payments), I had to keep within 1cent accuracy.

After reviewing the needed calculations, my main issue was the NPV (Net Present Value); although I am familiar with the formula and applications of NPV, I was not sure of the exact implementation in Excel.

So, I jumped to Google to see if there was any implementations and found the Excel Financial Functions for .Net: “… a .NET library that provides the full set of financial functions from Excel.”.

Great! BUT. The library is actually implemented in F# and only the source code is provided, no compiled version…. No problem, since all .Net languages compile into IL (Intermediate Language), all I needed to do was to compile the F# project and then reference it on my C# one.

After I add ed the Financial.dll reference to my project (compiled version included in the provided source code), I am ready to use it on my code, however, note that the following reference is required:

using

System.Numeric;

 

With the reference in place, I can now use the NPV function as follow:

Financials

Comparing the signature of the NPV function on Financial.dll to excel, we can see they are virtually the same:

Financials-Excel

And even though I have shown mainly the NPV usage, this library contains implementation pretty much all financial functions in Excel (Complete List).

There you have it; if you ever have a project where you need to use Excel functions, you can refer t the Excel Financial Functions for .Net library; you can use the compiled library provided on this example, but I recommend reviewing the library page regularly to check for updates.

Hope this helps!