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Archive for August, 2014

C# MemberwiseClone

Clone Trooper - Creative Commons License from https://c2.staticflickr.com/4/3484/3796528975_e8c7faaed2_z.jpg?zz=1

If you’ve ever needed to make a copy of an object in C#, you might have come across the MemberwiseClone() method. This can save you a lot of hassle of left-hand/right-hand property matching, but it does come with some “gotchas” that might not be readily apparent if you haven’t carefully read the documentation.

Let’s start with a class that looks like this. Notice that it has a ShallowCopy method that just returns a MemberwiseClone of the object.

Now, let’s create some objects and make a shallow copy of the worker and see if the objects are the same:

This gives us the following results:

“So what?” you might ask. Well, what that means is that if I change a property on the Boss of either object, it automatically changes in the other object (since only the reference was copied, and that reference points to the same memory address in both cases).

This gives us the output:

It is possible that you may be okay with this happening. However, if you don’t want this to happen, you can implement a DeepCopy on your object instead. In the DeepCopy, you take a MemberwiseClone and then you call for a deep copy on every reference type in the object. In our example, I’d add this to our Person class:

Now, when I check on the objects, they aren’t the same. And, when we change the property on the boss, it doesn’t automatically change in both places because they are completely separate objects.

That’s all there is to it. I have wrapped up the code for this blog post into a small console project and put it on GitHub. If you have any questions, let me know in the comments.

Podcast Episode 21 – Enough with the Religious Bigotry

Larry Wall Bigotry Quote

In Episode 21, I spend a little time on the “significance” of episode 21 before getting into the main topic. Our topic this time is about people who worship the language that they are using like a religion. Far too often, I’ve encountered the attitude from developers that people who aren’t using what they are using are luddites, heretics, and not worth their time. In my opinion, that has no place in today’s development landscape and I explain why.

Links Mentioned in this Show:

You can also subscribe to the podcast at any of these places:
iTunes Link RSS Feed Listen on Stitcher
In addition, my podcast is available on DoubleTwist and the Windows Marketplace.
Thanks to all the people who listen, and a special thanks to those who have rated me. I really appreciate it.
Listen here:

My First Guest Post – a Brief Bio of John W Mauchly

A little over two weeks ago, Matt Groves, my first podcast guest, asked for some volunteers to contribute to his excellent brief bio series.

I jumped at the chance to contribute. I find the history of our industry fascinating and while Matt had already covered one of my favorites, I was more than happy to grab the next name in the list and set out to work.

I read a lot of information and I learned a lot in the process. In the end, I had a lot of trouble even coming close to living up to the Brief label. My subject had done a lot to move computing forward. In the end, I was able to cut enough and still maintain a narrative that made sense and kept the importance of Mr. Mauchly. So, if you would, please go over to Matt’s blog and check out my guest post Brief Bio: John W. Mauchly.

Podcast Episode 20 – Russell Patterson on Simple Lookups, NuGet, and Coding in Public

Russell PattersonEpisode 20 brings us another interview podcast and this time I’m talking with Russell Patterson. Russell is the author of Simple Lookups, a .Net library for dynamically handling CRUD operations for your “type” classes.

Along the way, we talk about Simple Lookups, what it was like to make a NuGet package, decisions you make when you know that people you don’t know will read your code, and how he got to where he is today.

Links Mentioned in this Show:

Russell on Twitter and his blog
Simple Lookups on NuGet
Hotel WiFi Test
Code School
Building Cloud Apps with Microsoft Azure
ReviewCast
Listen To This Episode:

You can also subscribe to the podcast at any of these places:
iTunes Link RSS Feed Listen on Stitcher
In addition, my podcast is available on DoubleTwist, Swell, and the Windows Marketplace.
Thanks to all the people who listen, and a special thanks to those who have rated me. I really appreciate it.