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In this video we're going to be creating our projects that will receive user input and print some outputs.

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I'm starting from our folder where our project was created because maybe you shut down the machine you

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went to have dinner.

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It's been days since you were last in Visual Studio and so I just want to show you how you can relaunch

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your project from the file system and you know not to have to go into Visual Studio and source it so

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I can just go back to the file system find the solution and double click.

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That will launch results to you and that will relaunch our project our solution with our project and

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everything that we were doing.

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So every time you go ahead and you correct code and you save and you relaunch a solution it may relaunch

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with all of the tabs yard open or the court files and all the projects and everything that you know

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let's go about putting a new project inside this solution so that we can test or write a new program.

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So this was our hello world program notice at a comment here at some static takes or some random text

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that was giving problems that just come into default.

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But that's it for the whole world so let's move on to a new one.

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Someone to write the solution note not the project.

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This is the project I'm right clicking the solution so or I notice that it's really just a config file

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right.

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So I'm right clicking the solution and with the click add and then I'm going to see new project then

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it brings back this menu that we should be familiar with this dialog box that we should be familiar

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with asking Okay what kind of project do you want this time.

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So I'm going to select once again console up dot net core click next and then this time I want the project

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need to be input output so input outputs lots of spelling errors.

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So you want to make sure that you write it properly right.

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Naming is important.

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And then I click Create and then I get a brand new code.

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So notice it's kind of standard to come with hello world hello world is probably the first programming

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phrase that most people will ever learn when they're learning a new language how to print Hello World

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to the screen but that being said I just wanted to take some time to appreciate what is happening here.

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So notice I have a new program that seems file I still have my existing one and then so as not to make

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the mistake and let's assume that they were both identical they were both very new.

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Both of them had the same code in it.

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How do I know which one belongs to which project.

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So each time I have a console application or project you're going to get a program that's yes file and

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it's going to come with a main function and let's just say it's standard for it to say hello or that

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means we've seen that with the dot net core template we can use this dropdown list to look at which

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project it is in.

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So this program that ceasefire belongs to the hello world project.

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If I go to the next one you see that it belongs to the input output project.

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If I close them both and just does this file.

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That's a project file.

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And I have no files open then from the solution Explorer I can specifically go to which project I want

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and then select the program gutsiest file.

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All right.

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So that's all you can manage multiple projects and appreciate where what file is coming from so you

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don't make mistakes.

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Goes well you don't want to be writing input output stuff instead of hello world program dot.

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Yes.

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And then when you're running you're wondering why is your code not working or why isn't it detecting

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the code that you wrote.

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And that's just because you wrote it's in the wrong program.

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That's yes.

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So you want to be very careful and very attentive.

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And as you build more and more applications even more advanced applications you're going to have multiple

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projects we just want to be very careful unsure where each file is.

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Now let's get started.

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I did say that we wanted to write something to get user input and then print back to the screen so let

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me just remove.

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Hello world.

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So we're going to be learning a few things here.

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We're going to be learning about one variables to hold to prompt for inputs received from the user.

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And then three how to print it back to the screen.

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So let's get started with variables and I'll just put comment variables.

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A variable is like a little container.

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All right.

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So when we want data from the user we have to create a container and then we use a container to store

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the value that the user gave us.

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So for instance if I wanted a name then I need a variable and it makes sense to just call its name the

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name of my country and therefore somebody whose name is name.

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All right.

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And then further to that I need to define a type.

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So a type means the type of data that I'm expecting.

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So if I want somebodies name then that is text because they'll be writing letters.

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All right.

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So anything that's letters is a text type or a string.

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So in C sharp we call text types string when you want text from somebody you need a pocket or that container.

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And it needs to be able to store what we call a string or text.

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All right.

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So let's start off with all we declare a variable.

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I will first define the data type so C sharp eyes.

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Lots of data types and it's good to know when to use which one.

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So I just gave us a case study for the data type string.

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So I say string and then I give it the name.

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So I want some variable that is called True.

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Now it's called name sorry and it is often data type string you would have already noticed that you

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have something called string and args earlier.

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So that was the data type and args would be your variable name.

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So in this case we're making our own variable telling it that.

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OK.

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Declare a pocket in memory and call it name and it should be able to store anything that is a text.

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So I want name.

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That's one.

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So I'm going to see the clear variables and then you can have multiple variables.

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You can have as many variables as you want.

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Right.

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But then let's just keep it simple so we want name and then I'm going to want to store what the user

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is entering into the console in my pocket called names so I need to assign the data being collected

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from the console screen inside of me.

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So whenever I want to store data inside of that country you know we see a continued name or variable

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name.

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So this is name is equal to and then if I'm receiving input I'm going to call my console.

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So we get this glass console or remember that when we were printing the screen we had a console as a

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class name.

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So console once again and then I said dot and then this is all called intelligence where it's telling

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me all of the potential things I can do with my console class.

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So the thing I want to do this time last time we were writing a line.

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So if you scroll or use your right line and you see right but this time I want to read lines so you'll

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see that they have an option that is read line so I can double click that.

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And then the red line is appearing because it's saying oh yes he read line.

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But the context the syntax is not correct and that's because it's a function.

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So I need my open and close parentheses.

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Then I can use my semicolon.

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So I did say I would pay attention to the semicolon.

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Every line that you write must end with a semicolon.

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There are exceptions but for no let's just follow that rule.

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Every line that you write must have a semicolon.

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So we'll see the exceptions as we go along and relentlessly is just a matter of practice to get comfortable

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with when to use your semicolon.

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And when not to know after we've gotten the name then we want to print it back to the screen.

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So then I go to the next line.

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So this is.

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And let me just put the comments as I go along getting value from input or let me see.

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Yeah.

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Getting on store and getting and storing value from inputs.

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All right.

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So that's what we're doing in this line.

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Then the next line is printing value or values to console screen.

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So we've gotten the value and we've stored it.

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I know we want to print it back.

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So the cool thing is that I can store it.

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I can change a value and I can always manipulate whatever is in here before I printed book.

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And that's the value of having the the variables.

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So no I want to bring it back to screen and we did.

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We printed the screen already we did for intel world so we can just follow that same pattern and we

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see a console dot.

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And remember the print was right.

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Line and see intelligence is helping me right line and then it's a function so I need my parentheses

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and then they're coordinating me and telling me that OK what do you need inside here is a string value.

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So we did put hello world inside quotation marks and that's what a string is it's text like I said.

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So whenever one takes we need to open and close quotation marks and then we can type anything we want

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any alphanumeric sequence any special characters we want.

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Once they're inside of quotation marks see sharp we'll say Well that is static.

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I'm not supposed to touch that because that is what my master being you wants me to print.

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All right.

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So I'm going to remove this and I'm going to so I can put the sentence you know anything I want.

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We did see a Hello World last time but what I want to print is not static.

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I don't want to determine what I'm printing here because I'm receiving something from the user and I

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want to print what the user gave me.

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So instead of using my quotation marks and defining you know this is all called static.

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All right.

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So once it's static it can't be changed again.

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So if I type hello world then Hillary will be printed if I type my name manually then obviously I am

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bypassing whatever was inserted through the console because anybody can come and use this program put

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in that name and this will always just print tor Williams regardless of what values inside name.

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So what we want to do is print the value inside of name to the screen and the way that is done is to

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actually put the variable names.

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So console the right line and then we put in the variable and notice once again we need a string value

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but we do have a string variable.

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So there are two ways to get the string.

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We can use it as static meaning whatever at Whittier will never change until I come back in the code

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and change it or I can use a variable of type String.

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All right.

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So I just declared a variable of type String received some string input from some user and went to print

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it back to the screen.

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So once again every line ends with a semicolon a CDO studious I mean semicolon is expected.

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So I put that there and then I just run no notice that the start still has the hello world.

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So if I were only still just going to print Hello world it's just going to execute the hello world program

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we have multiple projects and at this point I want to run input output and not hello world.

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So what I need to do is change the startup project from hell world to input output.

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So I want to right click input output and then select the the option that is set start set.

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Start a project so I click that.

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And then notice that this is no bull.

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So before hello or loss board No this one is bull.

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So that's a nice quick way to know which one is a startup project and the notice that contextually the

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start button text also changed so I can just click input output.

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So my program is started and it's just going to sit there with a blank screen just blinking and waiting.

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So what it is doing is waiting on the redesign.

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So it already declared name.

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You're not going to see a visual cue of the variable being declared.

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You're going to forever read line.

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It's just going to wait until there is some input followed by an enter key.

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So if I put me with a fictitious name Archibald Gordon and then I press enter then it executes A.C.

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Archibald Gordon printing about the screen.

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No this is not very intuitive because it was just blank you were just waiting what exactly was it waiting

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for.

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So it's always good to give your user a visual cue to say Please enter your name or something like that

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right.

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So what I'm going to do is above this line where I am receiving data I'm going to put a console right

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line to print to screen the prompt.

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So we've got this up prompt so console Dot.

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Right.

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Line open braces are open parentheses.

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And then I want the static text that sees enter your name so I'm saying please I can say Please enter

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and name can whatever your prompt is.

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So obviously whenever you run a program or you use a program when you're filling out a farm on the Internet

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whatever it is you're doing on a computer.

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They always give you a visual cue to say this is the data I'm expecting to from you right.

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No.

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So I'm seeing enter your name and then this line needs to be for the best in the colon.

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And then I'm going to wait for you to enter your name.

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And then once you have done that I'm going to print your name back to the screen.

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So let's try that again all right.

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So no it says enter your name because it ran that consular line.

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Enter your name.

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I know it's waiting for me to enter some value so that again storage inside my variable and then printed

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back to screen.

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So this time I'm going to use Q Early figure in and then I'm going to press enter and then you notice

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it printed.

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Kimberly Fagan back to screen.

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So no it's still not very intuitive because I don't know which one is which.

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Okay I'm looking at a console.

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I see Kimberly figure and I just see repeated what what is the repetition for it's not very intuitive.

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They always want to put in visual cues to use us so that they know exactly what they're looking at at

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each point.

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So I'm just going to close this console and then all I'm going to do is putting on the console or Atlanta

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or put in more text in this console or line to make sure that contextually you know exactly what you're

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looking at.

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So what I'm going to do is add another console right line and then this I actually go into the console

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right.

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So the console dot I have a right line but you also have a right somewhat into our right.

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And really the difference between the right and the right line so right is going to see your name is

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and then semicolon and then we're writing once again.

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So the console the name that was entered.

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So let's try that again.

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All right so now we see it enter your name.

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So OK this time it is Paul Bishop and then we press enter and then we see your name is colon Paul Bishop.

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No notice that when we did console right line it automatically went to the next line and waited for

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text when we did console a dot right.

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It just did it in one line and then whatever as we wanted it stood in that line.

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So that's the difference between right and the right line right.

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Line automatically it's almost like you type a sentence in Microsoft Word and you press enter and go

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to the next line.

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That's what right line does for you automatically it just puts the next block of text in the next line

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automatically.

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However right will not meet that break it will just any other string that is to be printed will just

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be printed in the same line onto that line.

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You know it's the text wraps.

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You know we all should know what word repping is.

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So onto the takes the reps are on the screen.

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That's all right.

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Works.

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So that's the difference between console dot right and the console dot right line.

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So that's it for input output.

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So let's us do a quick review one we learn to declaring variables.

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Once again there are many data types that variables can have.

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We're just keeping it simple we're just getting started.

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So I'm just using string where I collect some text and store inside some variable called name then I

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prompt the user for them to enter their name and then once they enter it.

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So this is all we get input from the console.

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We automatically assign it to our variable having gotten and stored that value from the user.

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We then proceed to see your name is.

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So we're printing back some static sentence that's giving them a visual cue as to what the data is that

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we're printing.

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So we're seeing your name is colon.

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This takes will never change on this.

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I change it in the program but then we dynamically printed whatever name was entered because we printing

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by the value in the variable in the next lesson we're going to go through some more data types in C

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sharp and look at the requirements between collecting data from the console for these different data

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types and printing them back and what conversions need to be done.