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Edit - even though the steps described below related to an example with IIS, you can use this technique for any running process, it’s just a matter of identifying the process id.

Using Entity Framework I occasionally get the following error when reading from the database - `exceptionMessage=Value cannot be null. Parameter name: constructor` My Person class looked like this - 1 public class Person 2 { 3 public Person(string firstname, string lastname) 4 { 5 Firstname = firstname; 6 Lastname = lastname; 7 } 8 9 public Guid PersonId { get; set; } 10 public string Firstname { get; set; } 11 public string Lastname { get; set; } 12 public DateTime SomeDate { get; set; } 13 } There is no way for Entity Framework to know how to instantiate this object because there is no empty constructor.

Download full source code here. I thought this would be easy, there is a method called ExecuteSqlCommand which takes the stored proc name and an array of parameters. I wanted to pass in two parameters and get one back, no problem, I’ve done this with ADO.

The Problem It’s hard to get the details of an exception from a Web Api response when calling Web Api from a C# program. (Skip to the solution if you don’t care about the background), it even handles inner exceptions!

Short version If you are having problems with nuget packages and think it might be related to local caching delete packages from these directories - %LocalAppData%\NuGet\Cache and %userprofile%\.nuget\packages\ Long version I was making nuget package, lets call it Foo, for my own use, not one that I was going to distribute publicly, but I was putting in on MyGet.

Full source code to download. I’ve been using ninject for a few years, but every time I use it with Web Api I hit some problem and they usually stem from not including the right nuget packages, not changing the DependencyResolver or (once) forgetting how to make a binding!

Sometimes when using Entity Framework I want to verify that I’m connected to the database I think I’m connected to. Here’s how to check in Entity Framework 5, Entity Framework 6 and Entity Framework Core 1 (EF 7)

Full source code. I’ve been using AutoFixture for a while with my unit tests. It creates objects with prefilled data, saving me the hassle of manually constructing them. Basic usage If you want a string from AutoFixture do something like -

Summary When returning objects from a method try to use IList, IDictionary, etc instead of List and Dictionary. This is especially important when the method is inside a class library which you distribute.

Filtering out entries in a dictionary is not too difficult when the key and value are simple. For example if you had - IDictionary oneToFourDictionary = new Dictionary {{ "one", 1 }, { "two", 2 }, { "three", 3 }, { "four", 4 } };