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While writing my tips series and writing EF controllers for MVC I found that I regularly wanted to create and attach a stub entity . Unfortunately it isn’t quite that simple, you have to make sure the entity isn’t already attached first, otherwise you’ll
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Here’s a scenario which Damien and I encountered recently. We needed a way of specifying Facets for properties on Entities, i.e. things like Nullable , MaxLength , Precision etc. And we needed a class hierarchy because different types of properties have
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UPDATE: as Joe rightly points out in the comments (thanks Joe) when you try to pass a Func<T,V> to a method expecting Action<T> using lambda syntax it doesn't fail. Somehow the compiler must realize there is no match for Func<T,V> and
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I came to C# from Java, which I’m pretty sure doesn’t (or maybe didn't) allow this, so I was super surprised today when I learnt that C# method overloads can have different return types. So this class is completely valid: public class Foo { public Foo
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Having something enumerable is the gateway to all LINQ’s loveliness. But sometimes you have just one object. So how do you make that enumerable? var people = new Person[] {person}; Not exactly hard huh? In fact you can simplify this even more, you can
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I was debugging a problem a couple of days ago, when I learned something interesting. I had some code that looked like this: foreach(Employee e in manager.Manages) { … } The manager.Manages property returned a custom implementation of ICollection<Employee>
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Jarek has released his sample provider for Oracle here . In his post he talks about a few of the more notable challenges he had and how he got around them. If you are writing an EF provider this is gold!
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Today I spent a bit of time working on the data model for my fantasy soccer application. I don't want to talk about the actual model today though, because I'm not really ready. What I want to do is talk about a problem that occurred to me, namely Unit
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Yesterday I was talking to a Simon, another super smart dev on the EF team, and he raised a big concern, one that I am sure you can all relate too: We've all seen something like this: And thought: "What is the bare minimum I can do here to save a Whatever
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Michel Perfetti , has taken my little Maybe thingie and gone a lot further , by using expression tree re-writting he has made it possible to express this: string code = licensePlate.Maybe(lp => lp.Car) .Maybe(c => c.Owner) .Maybe(o => o.Address)
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But I only just realized that extension methods are cool for avoiding NullReferenceExceptions . We all know that if you have something like this: LicensePlate licensePlate = null ; Car car = licensePlate.Car; It will throw a NullReferenceException . However
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Okay so we've got to the interesting bit at last. We've hooked up our extension method, we've got a query for filtering the records we are updating, we've got a map from object Properties to database Columns. So now comes the interesting bit... We now
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Okay, okay, okay... yes I know this is the slowest moving series in the history of blogging (sorry Roger J). Now, when a blog post starts like that, you would probably expect the next sentence to begin with "But" or "However", not this time though, I
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So I was reading Wes' latest post about Monad's a while back (which incidentally is well worth a read, it is the first good explanation of Monad 's I've seen that uses a language I am comfortable with in it's examples, namely C#). Well one thing Wes kind
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Okay so it has taken me a while to get to the second part of this post... but as they say better late than never. As I've said before when designing this sort of API, I always like to start with the end in mind... this is what I want the Update() method
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