Dot Net What Not Posts

Published 10 May 2011

How to persuade a Linq query to include your child objects

When you use Linq to create a query against an entity framework model, a common scenario is to use the .Include() extension method to make sure that any child objects are also loaded. This is mainly useful when the results of the query are to be sent over WCF, where the client is disconnected from the source of the query, and so cannot go back to the database to pick up any child objects as needed.

This works fine for simple queries, but falls apart when you want to do anything clever, like joins or shaping.

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Linq

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Published 22 February 2011

Debugging WPF data binding

I was having some trouble with WPF data binding yesterday, where the binding looked correct, but the data wasn’t being shown. It turned out that I had forgotten an .Include() on the original query (this data is being sent across the wire through a WCF service, so I can’t use lazy loading), but along the way, I discovered a really useful blog post on how to debug WPF data binding.

WPF

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Published 23 January 2011

Seemingly innocent Linq problem that had me baffled for ages

I came across an innocent-looking Linq problem the other day that really had me baffled for some time.

It’s easiest explained using the ubiquitous Northwind database (although just about any other relational database would probably do). Suppose you want a list of customers with their orders. Pretty easy eh?

Erm no, it wasn’t!

Read moreSeemingly innocent Linq problem that had me baffled for ages

Entity framework Linq

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Published 19 December 2010

Design patterns

Although it’s not actually a .NET issue, I decided to blog about it anyway!

I’ve been looking at design patterns quite a lot recently. I have always been a “bung it all in the code-behind” kind of programmer, which is an easy way to program, but messy. You end up with spaghetti code that’s hard to maintain and impossible to test automatically (not that I ever tried mind you!).

I decided to learn some new skills, and discipline myself to programming the Big Boys’ Way. I dutifully went to Amazon and spent far too much on books, and sat down to read them all. Most were fairly tough going and dull. I was beginning to think it wasn’t worth the effort, until I came across Head First Design Patterns, which was a breath of fresh air. Apart from the slightly wacky style, the explanations were very good.

My only gripe with the book is that it’s very Java-oriented. Given that design patterns are language-agnostic, this is totally unnecessary. Most of the time it didn’t spoil the book, but in a couple of places it really annoyed me. However, it’s still the best design patterns book I’ve read by a long way.

I hope to blog more about this subject. Watch this space (unless you’ve got anything better to do of course!)

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Design patterns

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Published 15 August 2010

Passing custom and anonymous types across code boundaries

Linq is great for grabbing entity objects. The code is simple, and you end up with known objects that you can use.

But, when you want to deal with anything slightly off the beaten track, it gets a bit harder. For example, if you have a Linq query that returns an anonymous type, you can easily manipulate it in the same code block.

Here I detail an early exploration into the world of anonymous types

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Entity framework C#

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