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Coding 101 31
Shannon Morse: On today’s episode of Coding 101 we welcoming back one of our favorite code warriors, and we’re revisiting an old coding language favorite as well.
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Fr. Robert Ballecer, SJ: This episode of Coding 101 is brought to you by Lynda dot com; learn what you want, when you want, with access to over twenty seven hundred high quality online courses, all for one low monthly price. To try it free for seven days, go to Lynda dot com slash C one zero one; that’s L-Y-N-D-A- dot com slash C one zero one. And by Hover dot com. Hover is the best way to buy and manage domain names. It’s simple, honest, and easy to use. For ten percent off your first purchase got to Hover dot command enter promo code C one zero one eight. Welcome to Coding 101, it’s the Twit show where we let you in the wonderful world of the code monkey; I’m Father Robert Ballecer.
Shannon: And I’m Shannon Morse and welcome to this episode of Coding 101 where for the next thirty minutes we’re going to get you all coded up on everything you need to know to be an awesome code warrior.
Fr. Robert: That was very Game of Throne-y. You were getting all kind of dame-ish.
Fr. Robert: Nice. We’re doing something a little different with this module.
Shannon: We are.
Fr. Robert: This is a little strange.
Shannon: Be prepared for lots of questions.
Fr. Robert: Be prepared for lots of questions. But in the groups, in the emails, people were saying, you know, 101 is cool, I like the whole beginner thing, but it would be nice of every once in a while we could throw in something a bit more advanced. Because when we are stuck with the 101 level, we basically have to go over the same concepts, over and over, in every language.
Shannon: Because each language is very similar, it’s just how it’s put together that is a little bit different.
Fr. Robert: Right, and there is nothing wrong with repetition, there is nothing wrong with learning about variables over and over and over, because they are important, or loops over and over and over, because they are very important, but we thought, why not have a module or two every year where we kind of take a step back, use a language we already covered, and give you Coding 102.
Shannon: Oh boy. I hope you are prepared for me to ask you tons of questions, because myself, I feel like I am still a beginner, so I might get a little confused along the way.
Fr. Robert: That’s all fine, we’re good. We’re absolutely great for questions. Now first thing we have to do is we have to tell people we’re going to be using C#, the very first language we covered here on Coding 101. Now you may remember when we covered C#, it was all about those basics because it was the fist module, the first set of episodes for Coding 101, and we never really got past making functions, or methods.
Fr. Robert: That was good, but I think we can do better.
Shannon: Okay, I’m ready. But first, I think we should review how to reinstall Visual Studio. Just in case people haven’t done that yet.
Fr. Robert: Yes. This is something that we didn’t do the first time around; we didn’t give people a decent step by step tutorial on where they get Visual Studio, which is free, by the way, so they don’t have to pay for it.
Fr. Robert: And how they get it on their computer. If we could just put that at rest, so that people know that it really great, easy to download, easy to put on your, on whatever computer you’re using. Then at least we give them that head start.
Shannon: Alright, are you guys ready? So first off you need to download the specific version of Visual Studio for your computer. So if you run over to my machine here, I’ve gone to the Visual Studio dot com website; we’ll have this link in the show notes again, but if you don’t know where this is, it’s also found in episode two, from our show notes as well. So you got the Express Twenty Thirteen for Windows Desktop Visual Studio download link, you click right there, and this is available for Windows server, Windows Seven and Windows Eight. When this pops up you just simply that your system requirements are correct, and you got to Install Now. So you click right there, and that will reopen up a new page for you, and you click on this one, you want the Express Twenty Thirteen for Windows Desktop version. You basically just run thorough the onscreen instructions, it will ask you to login with whatever your Microsoft login name is; if you have an Xbox, you have a Microsoft login. After you run through that it will automatically install and open up for you. It takes about twenty minutes or so for the installation to progress, so just wait for it finish, and then you’ll be able to open it up. Now when you first open up a project, you’re going to go to File, New Project, and I have a question for you, Padre. Are we still doing Console applications?
Fr. Robert: Well that’s what we learned in the first module.
Shannon: We did.
Fr. Robert: We used nothing but the console. We’re going to be using something slightly different when we start classes and creating objects, but we’re going to let Lou show us that.
Fr. Robert: If they want to, and I would suggest they do this, if they want to run through the lessons of module one again, it’s all Console.
Fr. Robert: Use the Console, and copy and paste exactly the code that you see inside of our Get hub for module one and it will work.
Shannon: Yes. And then you can just simply run it by; I’ll cancel out of that; you can hit Start or you can go up here to debug to make sure that everything is correct, I’ll hit Start Debugging, it will go ahead and start for you, and then it will run your code. I don’t have anything right here yet, because I haven’t written a code yet to be put in here, I just opened up a brand new one, so it’s not going to do anything.
Fr. Robert: This is code that doesn’t do anything.
Shannon: Yeah, exactly.
Fr. Robert: So it will run, it will compile. So Irene, in the chartroom, makes a very good point, which is if you’re a college student, a current college student, you can get the professional version for free. Microsoft gives it to you. You do have to go through the verification like you have to do every time you purchase software.
Shannon: You when you have a dot EDU email or something.
Fr. Robert: Right, something like that. But if you are a college student, there is no reason why you have to use the express version. Something else I should mention is the express install, which you used, is nice, because it gets you up and running right away.
Fr. Robert: But you’ll notice that if you want to use some of the other languages that are included in the studio, or if you want to start using some of the modules that can be included, it has to download more. You can, there is a selection to download an ISO for Visual Studio Thirteen Express, it’s about four point seven gigabytes, so it’s big, it’s going to take a while to get, but once you have it, you can then put it aside, so if you ever need to reinstall, or install on multiple computers, or if you want all of the components at once without having to access the internet, that’s a pretty decent option.
Shannon: now, of course, if you guy are confused about any of this, definitely go back and watch our first module about C#. We did about eight episodes where they were all Console applications in Virtual Studio, and I think that will get you up and running in no time.
Fr. Robert: Yeah, yeah. Now speaking of up and running, I’m thinking on Know How with Brian Burnett, with Cranky Hippo, we always talk about filling the “knowledge hole.” Because there is that hunger people have for more knowledge, to know things, and Shannon. I’m just wishing that we had something like that here on Coding 101.
Shannon: I know a place. I know a really good place to go. You can learn software, you can learn how to do really good photography, and you can learn how to code, too.
Fr. Robert: That’s definitely going to fill my requirements for Knowledge Hole. Tell me about it.
Shannon: There is a website called Lynda dot com.
Fr. Robert: Boom.
Shannon: So if you are not familiar with it, Lynda dot com is the place to go to learn everything you want and keep you up to date on all the new software tutorials, all the new coding basics, and pretty much everything else you need to know, that you want to learn as far as computers go, you can learn how to make your own website, pretty much anything. So they help you learn and keep up to date with your software, you can pick up brand new skills, and you can explore new hobbies with their easy to follow visor tutorials. Whether you want to master the fundamentals of programming, or learn a new programming language like Python, which we showed here on Coding 101, or you want to design and develop engaging websites, Lynda dot com offers thousands of courses on a variety of topics. They recently released a new iPhone and an iPad app for iOS Seven, and they enhanced their Android app to provide Chrome Cast support, that’s pretty cool. Their iOS app includes a more visual intuitive interface, and both new apps offer offline courses and video viewing as well. So they make it really easy and really convenient to learn, even in environments without internet access. So if you are commuting, for example, and you have a drop out on your phone service, you can still watch offline. Lynda dot com users can also move seamlessly between mobile and desktop applications. So if you are moving from your computer at home to your mobile phone you can still watch while you are on the go. They also have a lot of new courses online, such as Android Essential Training, Creating Mobile Games with Unity, Wordpress Developer Tips, like Enueing Styles and Scripts, and Designing the Web, Pie charts with CSS. Ooh, that one sounds really fun. So for example, what Brian is showing online; Android Studio First Look, Android Essential Training. That would be perfect of you want to create your own apps, you want to learn a little bit about the background of using Android and how to actually improve your experience with that kind of software and Smartphones; perfect, absolutely wonderful if you want to design and develop your own applications. Now there are over twenty seven hundred courses and more added every single week, and all Lynda dot com courses are produced at the highest quality. So they are not just you know, homemade videos that you find on YouTube, for example, with terrible audio. These people that do these are accomplished professionals at the top of their field. They are passionate about teaching. And they have courses for all experience levels, from beginner to intermediate and those really, really advanced ones for you awesome guys out there, who already know a ton of this stuff. Now Lynda dot com works with software companies to provide you updated training the same day that new versions hit the markets, so you will always have the very latest skills. And you can watch from your computer or tablet, or your mobile device, whether you have fifteen minutes or fifteen hours, so each and every course is structured so that you can learn from start to finish. You can also search the transcripts to find quick answers, just in case you were watching and not quite paying attention enough, you can just search right down there in the transcripts. Super, super easy. And Lynda dot com also offers certificates of completion when you finish a course, which you can publish to your Linkedin Profile, which is great if you are a professional in your field. And it’s only twenty five dollars a month for access to the entire Lynda dot com course library. Or for thirty seven fifty a month, you can subscribe to the premium plan, and this includes exercise files that let you follow along with the instructor’s project, using the exact same project assets they do, and that is so important. And you can try Lynda dot com, right now with a free seven day trial; visit Lynda dot com slash C one zero one, to access the entire library. That’s over twenty seven hundred courses. Do it now, it’s free for seven days. That’s L-Y-N-D-A dot com slash C one zero one. And of course, we thank Lynda so, so much for their sponsorship of Coding 101. We love them.
Fr. Robert: And we are big fans of Lynda.
Shannon: We are!
Fr. Robert: Because we have said several times on this show, we understand that what we are giving the audience is just a teaser; it’s a taste on the various languages that we like to program in. You can actually use something like Lynda to fill in the gaps.
Fr. Robert: Fill in that knowledge hole, and actually move forward from what you see here on the show.
Shannon: There are tons that we can’t cover in the thirty minutes that we’re here per week, so go to Lynda dot com and fill in all those little gaps, with all the extra goodies for every single programming language. It’s totally worth it.
Fr. Robert: I’m all about goodies. Thank you, Brian just brought the knowledge hole up on the screen. Now I thought we should probably get to the ivory tower.
Fr. Robert: Let’s talk about it now.
Shannon: I have missed the ivory tower.
Fr. Robert: Right, there is something about; I love the wild card weeks, but when we come back its like, oh, yeah, ivory tower time again, we get to talk about stuff. When we talk about C#, of course we’re talking about an object orientated language. Now we talked about this again in the first module, I think it’s due for a refresher. Before object orientated programming, the way that you would code is you would code the process, and then you would consider the data right? So I code something…
Shannon: They were separate.
Fr. Robert: They’re separate, right. So we consider them separately. Here’s my code, there’s the data, and I run the data through the code, and I get something.
Fr. Robert: You know, very easy to do, very easy to see, but as the programs get bigger and bigger and bigger, it’s very difficult to maintain. And it’s not the best modeling of the world. You can go back to, again, the first module of Coding 101 and see how object orientated programming helps you not to think of code, but to think of problem solving.
Fr. Robert: That’s what object oriented programming really is. It’s: I have a problem. What do I need to solve that problem? Here are the pieces of data I need to solve the problem, and here are the functions, the methods, the code I need to solve that problem. Now that whole problem solving process is an object.
Shannon: This is why we got the object orientated programming.
Fr. Robert: Object orientated programming. Now again, before object orientated programming, you would just code and hopefully your data would flow through it.
Fr. Robert: But with OOP, it means that you get reusable code. Now you have the ability to create blue prints of classes and methods and use them over and over again. So I don’t have to rewrite something that I’m going to use multiple times instead of the code.
Shannon: It will just pull it in as soon as it needs it.
Fr. Robert: It’s going to pull it in when it needs it; it will get rid of it when it’s done.
Fr. Robert: That’s one of the nice things about object orientated programming. Which is handles all that sort of garbage management in the background. The other thing that’s really cool about object orientated programming is that it’s easier to understand. Because of our brains. Think about how our brains work. If you sat down and looked at thirty thousand lines of code, from start to finish…
Shannon: I would fall asleep.
Fr. Robert: First, you would fall asleep, but it would be ridiculously difficult to figure out what it does.
Fr. Robert: Right? Object orientated programming breaks that thirty thousand lines down into manageable chunks. So rather than saying, “This is program,” I say, “This is my menu, this is my user input procedure, this is my game procedure,” or whatever it’s going to be all the way to the end. So you break it up into little chunks that the human brain can actually understand. So it’s easier to maintain, it’s easy to understand, of course it’s easier to upgrade.
Fr. Robert: If you have ever been a programmer who had to deal with someone else’s code, you’re going to really like that.
Shannon: We all know what that is like. Make sure you guys comment.
Fr. Robert: Yeah. Now let’s talk a little bit about classes and objects, because we didn’t really get there in module one. We talked a little bit about methods and functions, which, by the way, we use those interchangeably. Now when we talked about functions, this was a typical function. Go ahead and go to my computer, Brian. This was just a know nothing function, right? We’ve got a public function, right, that’s going to give me an integer return, the function is going to be called answer, and it’s going to accept two variables, two integer variables.
Shannon: And they will be named int A and int B.
Fr. Robert: Int A and int B, right. And then the code inside the function is going to run based on the variables received. Integer C, so it’s creating an integer C, is equal to the value of integer A and integer B, which would be, let’s see if I gave it one and two, it gives me three.
Fr. Robert: Return C means that the function itself, the method itself, is going to return the value of three.
Fr. Robert: This is super basic function, right.
Shannon: Very, very simple.
Fr. Robert: Again, this is just brush up, if you watch module one, you should understand this. Go ahead and come back. Now when we start dealing with those functions that is sort of like the rudimentary entryway to classes, because classes aren’t really that much different.
Shannon: So, what is a class?
Fr. Robert: Well a class is; go ahead and go back to my screen. This is what declaring a class looks like. So Public; so again it looks like the declaration for that function slash method; it’s going to be a Public Class, and it’s going to be called C 101. And just like the function slash method, everything that goes between the two brackets is going to be part of the class. So in this instance, it doesn’t really look a whole lot different from a function, right?
Shannon: Right, yeah. It’s the same layout.
Fr. Robert: It’s the same layout and it’s actually the same idea. But, there is one big, big difference here. So when I’m talking about a class; go ahead and come back; when I talk about a class, I’m actually talking not about creating a construct within the computer’s memory, I’m talking about creating a blueprint. A class by itself doesn’t actually exist.
Fr. Robert: Yeah, okay so wrap your mind around this: what I’m doing, when I’m declaring a class; so let’s say I’ve written my class, and it’s got a bunch of variables, it’s got a bunch of methods, it’s got a bunch of procedures that I need to follow, right?
Fr. Robert: That’s just a blueprint. I can’t actually do; It won’t do anything.
Shannon: It’s not going to do anything, unless it has some kind of input.
Fr. Robert: Well it can’t even happen because it doesn’t actually exist.
Shannon: That’s weird.
Fr. Robert: You’ve got to wrap your mind around this, because this is the difference between a class and an object. People think classes and objects are interchangeable. They’re not. A class is the blueprint for an object.
Shannon: That’s very strange.
Fr. Robert: Well think about it this way: I am building a building, right?
Fr. Robert: I have the blueprints for that building.
Fr. Robert: Okay, if I have the blueprints for the building, do I have a building?
Fr. Robert: Because I haven’t built it yet, right?
Shannon: You just have an idea.
Fr. Robert: I have the idea for what the building is going to look like. The same thing goes for a class. When I am writing a class I am just writing the blueprint. It’s not until I create an object that that class comes into existence.
Shannon: Oh. Okay, that makes sense.
Fr. Robert: Think of it that way, right? But I’m going to drill this over and over and over again because this is one of the mistakes that people make mistakes on all the time when they are dealing with objects in programming.
Shannon: It kind of makes sense because it’s a little confusing.
Fr. Robert: It is, right?
Shannon: When you look at the code, you’re like, okay, looks the same as, you know, a method, so what’s the difference?
Fr. Robert: So what’s the big difference? Well we want to make a blueprint that we can make multiple instances of, we can create multiple objects.
Fr. Robert: Now think of it this way: I create an object; I’m creating it from a class. But if I have a class it’s not necessarily an object.
Shannon: Okay, yeah that makes sense.
Fr. Robert: Does that make sense?
Fr. Robert: Okay. Now let’s actually talk about what goes in a class. What goes inside of a class is pretty much anything. I can put anything in it. I can put variables, I can put methods, I can put procedures, I can put fields, but again what we’re trying to do with object oriented programming is we’re trying to make it solve a problem. So it’s going to model something in the real world I want to take care of. And it’s going to combine both my code and the data that’s necessary to solve that problem, okay?
Fr. Robert: And once I I have the blueprint for that problem solving process, I can make as many “objects” or as many “instances” of that class as I need.
Shannon: That makes sense.
Fr. Robert: Right.
Shannon: Okay, I got it so far.
Fr. Robert: You got it so far and really it’s not that different from making a function, making a method. It’s the same idea; it’s just on a grander scale, okay?
Shannon: Ooh, this sounds fun!
Fr. Robert: Yes, yes. Now so we already showed you how to define a class, let me show you how you actually create an object. So this is going to look a little weird. This is the keyword right here: new. C# recognizes “new” as a way to create an object. And in this particular instance this is what’s happening. I’m doing C101 so it knows I’m going to be using the class I just created, called C101, and “object one” gives me a way to reference that new object. Okay?
Fr. Robert: And this is the killer: it doesn’t actually create the new object until I write this part.
Fr. Robert: If I wanted to, I could just do this part: C101 object one; and it will know that object one is reference to an object based on the blueprint of C101, but there would actually be no object named “object one.”
Shannon: Oh, that’s weird. Okay. Because you haven’t created…
Fr. Robert: Because I haven’t created it yet. This is what I created: I used the keyword “new,” and then I say “C 101” and then open and closed parentheses. That will go ahead and create a new instance of that object. Now if I wanted to, I could do this multiple timers. I could go “C101, object two equals new C101 open closed parentheses close.”
Shannon: So then it would know that you are creating a second one called, with object two.
Fr. Robert: Right, with object two. Now its object two, and I can do object three; and it doesn’t have to be “object,” I can call it anything I want.
Fr. Robert: I’m just trying to keep this neat. But this is where the power comes into play because depending on what I’ve got in that blueprint, I could have just created a brand new object that does incredible things.
Shannon: All sorts of things.
Fr. Robert: All sorts of things. But I could make as many instances of it as necessary.
Fr. Robert: Right?
Shannon: And then it will just go back and call that same code, or whatever that object…
Fr. Robert: It will create a brand new one. In memory, it actually creates a new one in memory.
Shannon: It creates in memory.
Fr. Robert: So remember, like the blueprint and the building?
Fr. Robert: The building now exists. So when I do that process, when I say “new,” then “C101,” it’s creating a building.
Shannon: Creating a building.
Fr. Robert: Yes. So it takes the blueprints, it goes, oh, okay…
Shannon: So it’s like The Simms.
Fr. Robert: Okay, yeah, yeah. Actually it’s very much like The Simms. The whole idea is: this is what I’m going to create; I’m going to create a copy, boom. Boom. But just remember the blueprint doesn’t actually exist.
Fr. Robert: I cannot access anything in the blueprint unless I have actually created an object from the blueprint.
Shannon: Okay. Very strange but I get it.
Fr. Robert: You get it, and you know what, it’s going to get easier. Because as we start to talk about objects, you’re going to see why we want them.
Fr. Robert: You’re going to see why it’s really good to create them, rather than making a jumble of code.
Shannon: So weird.
Fr. Robert: It is, it is kind of weird. Now this is the time when we are going to bring in a code warrior.
Fr. Robert: Who is actually going to show us how this all works. But before we do that, I thought we maybe should take some time to talk about the second sponsor of this episode of Coding 101, what do you think?
Shannon: I think I’m ready.
Fr. Robert: I think I’m ready too, because…
Shannon: I like sponsors.
Fr. Robert: It’s Hover.
Shannon: Hover is awesome!
Fr. Robert: What Hover is all about; Hover is awesome! Hover is all about is taking all of the burden of registering your domain name. If you’ve ever had to; what did they say?
Shannon: I get huge headaches when I have to register domains.
Fr. Robert: Always, right?
Shannon: Oh my gosh.
Fr. Robert: Why? It’s because you can never get the name that you want, you can never get the version, the TLT that you want, dot com, dot org, dot net; in fact, space on the internet is much like space in the real world, where it’s all about location, location, location, right? I mean, you could have the greatest idea ever, but if you’ve got “Snubs dot Shannon Morse dot 12356 dot net,” no one is going to find you.
Shannon: That’s why nobody is going to my website.
Fr. Robert: That’s why no one is going to your website. Well Hover takes that burden away from you and they make it easy for you to get the domain, the great domain, that you want. Now when you have that great idea and you want to secure a domain for it, I suggest you check out Hover. They give you what you need to get the job done. You will find the perfect domain for your idea so that you can get started working on it, rather than worrying about that internet real estate. Right now Hover is having a sale on all new domains and extensions through September first. This sale is for new and existing customers. Summer is the perfect time to start a new project, and every single domain is deeply discounted, so you can choose whatever you like: dot com, dot ninja, dot guru, just about anything. People love hover; geeks, designers, developers and programmers love Hover because they know that they have the best tools and support. You don’t have to be an expert to get a domain, because their service is really that simple. They take all the hassle and friction out of registering a domain. It gives you easy to use, powerful tools to manage your domain so that you can do it right. You can get the perfect domain name and start building your web presence right away. All you have to do is search a few keywords and they will show you the best available options and suggestions. It’s actually, it’s a fantastic process to see, because sometimes you have your heart set on a domain and you can’t get it, you’re disgruntled, you start going through Hover and you will go, “Oh no, no ,no, that one’s better. I like that; let’s do that, let’s do that!” But they also offer you a valet transfer service to make the transfer process painless. If you are stuck on a registrar that you hate, Hover will actually take that away from you, rather than having o deal with call backs, and the pain and the hassle, they will use their valet transfer service to take care of the whole process and let you know when your domains are settled in your new Hover account. And they will transfer all your DNS settings so you don’t have to worry, even if you have a lot of domain names, it’s no additional cost, it’s no additional muss, no additional fuss. Now my big thing is that they are honest. They don’t believe in heavy handed up selling. They don’t promise you a super low price and then sock you with fees. You get what you paid for, what you agreed on. They include everything you need so that you can get exactly what you need to get at the time you need to get it. They also include custom email, and you get a smart control panel, so you can do what you want with your domain, and they include Who Is privacy for free on every domain that supports it. If you ever need it they have the best customer service support around, it’s known for its no hold no wait no transfer phone service. When you call a real person is ready to help. And now they offer you volume discounts. They will give you a discount on your domain renewals, starting at just ten domains, and then going up in value from there. The idea is, the more domains you have on your account, the less you will have to pay to renew them. So here is what we want you to do: Visit Hover today to register name, and for ten percent off your first purchase. Take advantage of their summer sale now, go to Hover dot com and use out promo code C one zero one eight. We thank Hover for their support of Coding 101. Boom.
Shannon: I’m ready!
Fr. Robert: Ready?
Shannon: I’m ready!
Fr. Robert: Now we welcome back to the show someone who, you know he has a special place in our heart because he was our first code warrior and it’s so nice to have him back, teaching C# as he should, ladies and gentlemen; do we have a drum roll? Mister Lou Maresca! Lou, thank you for coming back to Coding 101. And we have no audio.
Lou Maresca: Of course, I had to meet myself, right?
Fr. Robert: There we go! Let’s do it again; drum roll! Lou Maresca, thank you for coming back to Coding 101.
Lou: thanks for having me back, guys.
Fr. Robert: Lou, we’ve missed you. We’ve had some really good guest here on Coding 101 but you were out first, and you do have that special place in our hearts.
Shannon: Just like I do in my mom’s heart, because I was her first child.
Fr. Robert: Aww.
Lou: Love being here. I’m actually excited we get to do some more advanced stuff here, so that’s great.
Fr. Robert: Yeah, you were kind of chomping at the bit the last time because you wanted, you really wanted to get into some of the more advanced stuff, but we had to cut it because it’s like no, we’re out of the realm of 101. So now we get to leak over into 102, and of course, 102 had to start with classes. It was the thing that we didn’t cover last time, the thing that I think I most regret, because they are important.
Shannon: I’m Scared! I’m so scared, take it easy on me!
Fr. Robert: So Lou,
Lou: We’ll go slowly.
Fr. Robert: Can you run us thorough the entire process of creating a class?
Fr. Robert: Because it sounds daunting. We have given them the theory, but now they need to know how they actually do it.
Lou: You bet. So one thing we should know, too, maybe take a quick step back, is what a class is in C#, is a type, and we talked about type a long time ago in the first couple episodes, is basically just a variable, or a placeholder to store values. And that’s how C# kind of handles things; it handles it with different types. And there is what we call classes, and there is what we call structures, and we will talk about that later, obviously, and there are other things, too, different types. Like structures are like value types and classes are reference types, but we’ll talk about all that later as well. But classes are just a specific type inside of C# and it allows you to kind of do stuff, and store stuff, and change things, and do things, and that kind of thing, just like you’ve showed so far. So let me show you my screen, and I’ll show you how easy it is to create a class in C#. And just got “Quick Project,” just like you showed before. We will use a Console application, call it something, and create a route. And so we have this program. So what I would do real quick is normally they create a class already, which is what we use for our program, it’s just our base class called “Program.” And inside it has a main function that actually allows you to kind of put stuff in here. We did this before, we said console right line, we put a bunch of stuff inside here.
Fr. Robert: Right.
Lou: And this is just, again, what the class will run right out of the box, it will basically just only run this main function off this class. But we want to add our own class, let’s say we wanted to add a class called; so what we basically do is you go over here and you say, “I want to add a new class.” So “add” and you could do “new item” or you could go down here and actually just choose “class.” I’m going to do “new item” so you can see what else you can do here.
Shannon: Are these built in?
Lou: Yes, this is all built in stuff you can add, there’s obviously lots and lots of extra stuff that we haven’t talked about yet, but we’re just going to stick with the class for now, it’s the top one here. It’s actually under, now this is all the stuff that is under all the other separate things over here, all these other separate categories. I’m just going to chose “code” so it kind of narrows it down to just a couple things. And you will see there is a class item there. And down here it will already give you kind of a class name for it. And I’m just going to create a class called “animal.” So with this we can kind of understand how classes work. Hit “add” and now you notice over here the class is added to my little project file that we have here; my project just has a bunch of stuff in there, it has my “program” class and now my “animal” class. Pretty easy. And again, it has some additional stuff on the top up here; we can kind of ignore this for now. But again, what we are really paying attention to is the fact that it’s class. And so one thing we should note, too, is classes, they have this ability to have what they call, whether they are private or public, and what I’m going to do, I’m going to make this one public for now. So this way I can kind of see all over my program and be able to use it no matter where I am at. It’s just as easy as that. So I go back and as Padre showed, he said if you want to create an object, or a version of that, I can do that. So I can put “animal equals new animal” and boom now I have an object that is of that type “animal.” And it’s a class. It’s an object version of that class.
Fr. Robert: Right. And you could make as many copies of that class as you need, as many objects based on that class just by going “animal one equals new animal; animal two equals new animal,” as many as you need to finish your program.
Lou: Exactly right. And one of the things with classes, they are pretty unique. They allow you to do things like, if I wanted to create a type of animal, I could do like, “duck” and I could say you know, “it’s also an animal.” This is, we’ll get into what this is later, but this is called an “area” and so this is basically saying, “I had this thing, it’s a base thing, of all things, it’s a base of all things, it’s called an animal, and now I have a duck, which is actually a type of animal.” So I’m going to use that. So now if I go up here, I could do “duck,” and if I look inside of it; actually I’m going to try something else really quick. I’m just going t o add a, we’ll talk about this, too, but this is called a property, so if I put “number of legs;” oops, I’m typing as fast as I can; and then if I pop over here, if I actually look at “duck,” now it has number of legs in it. I didn’t put it in “duck,” I actually put it in “animal.”
Shannon: But because “duck” is part of class “animal,”
Lou: That’s right.
Fr. Robert: So Lou, again, I think this bears repeating. What you have done, is you used inheritance to essentially make a new class based on the original animal class…
Fr. Robert: And you have added properties, fields inside of that class, which do you remember?
Fr. Robert: In the first module, how you could start typing something and it would tell you what your options are, right?
Shannon: Yes. I remember that very well.
Fr. Robert: Well if you are using this class, it will give you the options for all the methods and variables that you have put inside of that class.
Shannon: That’s really cool. And it would make sense that it would be included in anything that is also part of that class.
Fr. Robert: Correct.
Shannon: So you could put “horse” and “pig” and you would still see “number of legs” in each one of those because they would still be part of “animal.”
Fr. Robert: Right. And what Lou is showing us is super, super powerful, because what it allows us to do is say, “Okay, this class right here, this blueprint, is going to be the basis for everything I’m going to do, but I’m going to have to modify it slightly to make it work for my purpose.”
Shannon: It’s kind of like having a bunch of remodeled homes, and every one is going to be slightly different.
Fr. Robert: Everyone is going to be slightly different, slightly different. But the important thing is you don’t have to do all the work, again, for every single home, for every single instance. It’s just like, no, no, no, no, this is that class, it just has one little change.
Shannon: I like that.
Fr. Robert: Very powerful. Okay Lou, keep going.
Lou: So one thing to note too, is I want to talk about too, is the reason why I use “duck” as an example is its actually important; because C# called a “static,” or a strongly typed language. And what that means is that when you have a variable and you give it a type, or basically telling the program, when it complies and does all it’s magic under the hood, it’s telling it to go and check it, to make sure that I can only store specific things in that variable. So like for instance, if you show me that screen again real quick, if I try to say that the duck has a number of legs, normally I’m going to put a number in there. So if I put a number, it’s like, oh yeah, that’s right. You put a number in there; it’s not going to give me an error. But I try to stick in there like a text, like this, it’s going to say, if I try to build this, it’s going to say no, no, no. you can’t convert a string, or a bunch of characters to a number, it’s not going to work out. And the reason is because that’s what they call a “static” in a strongly typed language like C#, because it’s going to check for those things. So it’s kind of like security in your coding. Now there are other languages that are what they call “dynamically typed,” or “duck typing,” they like to call it, and the reason why they call it that is because if it walks like a duck, talks like a duck, it’s probably a duck, and that’s because at run time it figures out what type it actually is. That’s why I want to make this example here, explicitly telling the compiler, or C#, that this is a duck, and the duck has some legs, and the legs are a number. And now it can check all that stuff once it compiles.
Fr. Robert: You know, it’s kind of refreshing, because the last two modules we have done have all been very IDE light, they haven’t really had an integrated developer environment, whereas C# has a very strong IDE. Whereas with Python or Perl, if we made a mistake, we would just see…
Shannon: We wouldn’t know where the mistake was.
Fr. Robert: We wouldn’t know where the mistake was.
Shannon: Because we have to fix it.
Fr. Robert: If you’re looking at the IDE for Visual Studio, it will actually tell you when you have mistakes, it will tell you, “Oh, no, that’s recursive, I can’t do that.”
Fr. Robert: Or it will tell you, “You’re calling on a property that I don’t have, so I don’t know what you want me to do.”
Shannon: Yeah, it makes sense. I wish every one would do that. Although I guess they could if you put them in the correct type of Gooeys.
Fr. Robert: Yeah, but remember the other reason we are also doing Visual Studio is because Visual Studio, once we get the hang of this, now I’m hoping we have time to get there with Lou, we could use this to say, create a mobile app. Because the Gooey is going to let you start using classes that are written for mobile devices, it will let you figure out what things you can play with, what devices I can access.
Shannon: You mean I could make my own video game on my Android about cats?
Fr. Robert: Sure.
Shannon: How many cats? How many legs does a cat have?
Fr. Robert: You’ve got to see someone about this cat problem. You really do. Alright Lou, I’m going to be the people here, and say, “Wait a minute, wait a minute Lou. When I wrote a function, I got the same thing. When I wrote a method in C# in module one, it would also tell me, I could call the function and it would give me the little hints on what properties I could add to this,” what does a class do that a method doesn’t?
Lou: So a class kind of encapsulates everything, right? It’s something that describes a thing that does things. And so the members inside of it are things that describe it. For instance, the properties are going to give it some properties and descriptions of that thing as method or functions. And those methods and functions are going to actually let it do stuff. So let’s say I wanted my animal to move, right, so I give it a function, or this is a method, in C# we call it methods.
Fr. Robert: By the way, let me clarify this, because we had this problem in module one, functions or methods, I don’t care what you call it, they do the same thing. In C# we call it a method, but we’ve also call it a function because in all of programming we know them as functions.
Lou: Sure. So one thing to notate is let’s say I want to add a variable in here, and this is the key here, this is the parameter to this function. It’s basically saying I, “I’m going to move and I’m going to have a specific speed.” But in the duck’s case, I want to move too, but instead…
Fr. Robert: Override, I love it.
Lou: Yes, I’m going to override it and instead I’m going to say, you know what, he actually flies.
Fr. Robert: There we go, there we go.
Lou: So normally the move would do something else, let’s say maybe this would say up here, he runs, a normal animal might run, but in this case, this animal, he’s going to fly, I want to make sure I put this in there, too. So now if I run over here and I say, I want my duck to move, and I say he moves really fast, let’s say about one hundred, right, now if I were to run this; really quick I’ll put a bullet point break right there.
Fr. Robert: This is what happens if you do it in real time.
Lou: That’s right. It’s telling me actually, this is what the compiler is saying: it’s actually not marked; you can’t override this thing, because it’s not marked correctly.
Fr. Robert: Right.
Lou: We’ll talk about what that means later, but I’ll mark this.
Fr. Robert: I don’t want to freak them out too much.
Lou: Right, don’t want to freak them out too much. One thing is now it says “flies,” right? But if I were to basically just create an animal though, and say “animal, move, speed,” let’s also put him going one hundred, and run this. It’s kind of small, I apologize, but the animal runs, and the duck flies. So that’s kind of the key is you can create a base class that does a bunch of things, but then you can, again, like Padre said, you can copy that functionality, but you can also change it. So you can say, “I don’t want to do what that base one does, I want to override that and actually make it move a different way, so I’m going to make it fly.”
Shannon: That’s cool.
Fr. Robert: Of course, we are using really super simple examples, here. We could see the entire class, and we could see the entire inherited class, on less than a page of code.
Fr. Robert: But once this starts getting complicated, I mean, once you write a class to access the screen on a mobile device, it’s going to be big, it’s going to be really, really big. And you may want to say, “Hey, guess what? That was the default class to access a screen; I need to create an inherited class, because I need to access it on a specific Android device; and we all know Android is a little bit different. So this is for this device, and this one is for…
Shannon: Make it a little more specific.
Fr. Robert: A little more specific. I override the specific parameters that need to change for that device. The nice thing about that again, is I don’t have rewrite the entire thing, I just say, “Oh, ninety nine percent of the code will be the same, it’s that.”
Shannon: That one little bit.
Fr. Robert: That one little thing. And rather than writing an entirely new class, I just inherit it.
Shannon: You don’t want to change it in the entire class. That’s cool, I totally get it.
Fr. Robert: Yeah, Totally makes sense.
Fr. Robert: Now Lou, we do need to stop, because we are running out of time here.
Fr. Robert: What are we going to do next time?
Lou: So I think we are going to go a little deeper into different types, and we’re going to talk about things called interfaces, and they are another version of a type in C#. And maybe we will go into some of the functionality in Visual Studio and how to add features to your program too. So I think we will get a little more into that so you guys can kind of understand Visual Studio as an IDE, like you were talking about, and give you a little more feature set.
Fr. Robert: Yeah, that’s actually really, really important. We’re not going to have regular homework for you, because what we want you to do is we want you to go ahead and download the IDE for your device, like Shannon showed you at the beginning. Now she showed you Windows eight, but if you go back into module one, she also showed you how to use, what was it for Mac, it was mono…
Shannon: I forget the name.
Fr. Robert: Mono Develop. It was something along the lines of that. But there is an IDE for Mac users as well. So find the one that you need for your device, and next week we will actually give you homework.
Shannon: Oh, I’ll do homework this week, though.
Fr. Robert: Lou, thank you so very much for being our code warrior, thank you for actually showing us how classes come into play, it is such an important topic, so I don’t mind burning an entire episode so that we get into people’s heads what it is, why it is important, and how you use it.
Shannon: It was worth the thirty minutes, or forty five.
Fr. Robert: Lou Maresca, the senior developer at Microsoft, we thank you. Can you tell the folks at home where they can find you in case they want to see what you do in between your appearances on the TWiT TV network?
Lou: You bet. It’s Lou MM Twitter, and you can check me out at CRM dot dynamics dot com, that’s all the work I’ve been working on for the last several years.
Fr. Robert: And we love you and it’s so good to have you back. We’ll see you next week. And also, we’ll see you next week.
Shannon: Yes we will.
Fr. Robert: That’s right, next week we’re hoping you will have your computers fully equipped so that you can get the lessons. We know it’s always a little jarring any time we start a brand new programming language, especially one...
Shannon: It’s exciting!
Fr. Robert: It’s exciting, right.
Shannon: Don’t be scurred!
Fr. Robert: Don’t be scurred.
Shannon: Get ready, we’re going to do some C#.
Fr. Robert: Yeah. But seriously, this is a heavy programming language, because it’s not like Perl, or like PHP, sorry, Python, where you can just write it in notepad, you do need to use an IDE, it’s going to take some getting used to, so please spend the next week sitting down and playing . Find in out examples from module one, play with functions, play with methods, play with variables, output things to the screen, get things back from the user, because you need to have all of that as a basis before we continue in this 102 module.
Shannon: I’m ready.
Fr. Robert: Alright now, in case they get freaked out, they can find…our TD is strange.
(Technical Director): What, you don’t like that?
Shannon: Don’t be scurred.
(Technical Director): Don’t be scurred.
Fr. Robert: If they want to find out show notes Shannon, where do they go?
Shannon: You can go to TwiT dot TV slash code or Twit dot TV slash Coding one zero one, all of that goes to the same place, where you can find every single episode that we have done. You can go back to the original C# module for Coding 101. You can basically walk yourself through and get caught up with everything we are going to be talking about on this module. That’s also where you will find the link to our Get Hub, we have all the original code from the first module in our Get Hub, so you can go there, find module one, and download and copy and paste all those different codes that we did for C#, and you can run them on your own machine and play with them to get an idea of what each and every one means.
Fr. Robert: Right. And you don’t actually have to download the episodes, if you want to, you can just look at the Get Hub. Because if you can just copy and paste the code from the Get Hub into the console, it will run. And once it starts running, what do we like to say? Break it!
Shannon: Break it! Yes, play with it.
Fr. Robert: There is nothing you can do to destroy the computer by running code unless you get really, really brave.
Shannon: Make it get errors and try to figure out why those errors exist.
Fr. Robert: That’s how it works. And if you get stuck, the best place to get help is out Google Plus page.
Shannon: Love this place!
Fr. Robert: We don’t have a shortener anymore, that kind of broke.
Shannon: I made a bitly, I made a bitly.
Fr. Robert: What is it?
Shannon: Bit dot L Y slash TWiT coding one zero one.
Fr. Robert: Go there, bit dot L Y slash TWiT coding 101, we’ve got over a thousand users in there, and they are users of every expertise. You’ve got beginners, you’ve got intermediate, and you’ve got experts, so go ahead and ask your questions. Or, if you are an expert already, help those people who have questions. Remember, it’s up to you to make sure that we get the next generation of code monkeys.
Shannon: And where else can we be found?
Fr. Robert: I don’t know, maybe that little thing called Twitter?
Fr. Robert: Yeah.
Shannon: I’m Twitter dot com slash Snubs; at Snubs.
Fr. Robert: And I’m Twitter dot com slash Padre SJ, and you’ll find me at, because it’s a huge fat symbol…
Shannon: And you can always throw questions at us over there, we’re always on Twitter.
Fr. Robert: We’re always on Twitter, and you get to find out what we do in between episodes of Coding 101. Which, by the way, we do live every Thursday at eleven o’clock, no, at one thirty PM pacific time; I’m stuck on my other show.
Shannon: I wasn’t aware it was so early.
Fr. Robert: Yeah, no, I never wake up this early. At Live dot TWiT dot TV, go ahead and jump in, and as long as you‘re there, we’ve got a chat room, right?
Shannon: We do, yes, it’s IRC dot TWiT dot TV and we have tons and tons of people in there asking questions, so we try to throw them out during the live show so you can get your answers right away.
Fr. Robert: Until next time, I’m Father Robert Ballecer.
Shannon: I’m Shannon Morse.