The implementation of the singleton pattern is pretty easy. However, despite the simplicity I see often that the pattern is being misused or implemented wrongly. What I’ve seen so far: The implementation is not thread-safe. (coding issue) Tight coupling: The business code/logic accesses a static property of a class in order to utilize the singleton… Read More »
Yes.. this ist just another blog post about IEnumerable and IQueryable. But the topic is quite important and I think it worth discussing about both approaches. Recently I had a discussion with a software architect about the implementation of the repository pattern. The question was: Should the repository return IEnumerable or IQueryable? So let’s do… Read More »
In one of our projects we had to transfer large data from the server to the client WPF application. In the beginning we had some performance issues. Therefore we decided to do some comparisons between ASP.NET Web API, WCF (with and without protobuf-net). The configuration: ASP.NET Web API WCF (Protobuf) WCF – Protobuf serializer –… Read More »
After coding unit tests the whole day, I decided to create a nice Visual Studio snippet which helps me to write the test method quicker. I usually structure my unit tests like this: public void Validate_ReturnsFalse_WhenStringIsTooLong() { // Arrange var expectedResult = false; var watheverMock = new Mock<IWathever>(); // Act var validator = new Validator(watheverMock.Object);… Read More »
In my current project I had to generate a Entity Framework query based on some search criterias defined in a dictionary. The structure of the dictionary was similar to this example here: var searchCriteria = new Dictionary<string, List<string>>() { { "FirstName", new List<string> { "Darko", "NoName" } }, { "LastName", new List<string> { "Micic", "Müller",… Read More »
Recently I had to build a very dynamic DataGrid in WPF, in which the columns were constructed dynamically. And some rows did not contain data for each generated column. I stored the dynamic values in a dictionary and bound the dynamic columns to the indexer property. The problem was that the dictionary throw an KeyNotFoundException… Read More »
Every .NET developer has already used an Ambient Context without knowing it. A typical Ambient Context is: using (var tx = new TransactionScope()) { …. } The pattern is not very well known. Here is one good description I found: The Wandering Glitch – Ambient Context I found this pattern very useful for displaying progress/busy… Read More »
In one of my projects (WPF, WCF) we are working with server and client side entities. Although the entities look very similar, we had some reasons to separate them: – Client side entities require more logic -> Implementation of INotifyPropertyChanged -> Implementation of IEditableObject -> Restore handling (When user cancels edit) All these functionalities were… Read More »
Data Annotations provide a very nice way to validate the entities. But under some circumstances, you may don’t want to validate all properties. For example, a property like “createddate” we don’t want to validate in the client layer, because the field is not set at this point. In this situation it would be good to… Read More »
I wrote a very tiny MVC Application Framework which runs on OWIN. This Framework uses the Razor engine for the view rendering. It’s very fast because the overhead is quite small. There are just a few lines of code which are between the Owin HTTP server request and the application logic. For that it doesn’t… Read More »