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‫Welcome back.

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‫And this video.

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‫I would like to teach you about string manipulation.

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‫And that's going to be quite important because you are going to need it throughout your coding experience

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‫and career.

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‫So this is an extra lecture where we are going to talk about the different ways of printing data on

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‫the screen, and we're going to look at composite strings, string formatting, string interpolation

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‫and verbatim strings.

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‫So of course you can stick to one way if you prefer one, but if you like all of them, then it's fine.

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‫But try to stick to one style throughout your project.

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‫So let's first of all define a few variables.

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‫So inside of my main method, I'm going to create two new variables.

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‫One is going to be H, and then the name will be Alfonso.

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‫So we have an integer in H and the string name.

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‫Now let's first of all use string concatenation and I have covered this keyword before.

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‫Let's look at this real quick.

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‫So here we are using string concatenation where we say, hello, my name is and then the plus sign,

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‫the variable plus and then another string, so to speak, plus another variable plus another string,

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‫so to speak.

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‫So we have used this in our double integer example where we basically said what kind of variables we

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‫are adding together in order to get a sum.

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‫So this is string concatenation, so let's run this and look at it and we will see it says string concatenation.

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‫Hello, my name is Alfonso.

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‫I am 31 years old, so this works flawlessly with integers as well as with strings here.

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‫So this is a string and this is an integer and we are using it in string concatenation and there is

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‫no problem with it in our console.

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‫Right line statement here.

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‫All right.

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‫Now let's look at the string formatting concept.

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‫This is going to be a little more advanced, so let's look at it.

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‫So string formatting uses the index.

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‫So here I have a statement that says that this is string formatting.

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‫Then we also use Hello, my name is but this time we don't end the string and use concatenation, but

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‫instead we're using curly brackets, then index zero for the first entry and index one for the second

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‫entry.

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‫So what we are saying is whatever is going to come after this comma here after my string at position

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‫zero.

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‫So the first entry will be positioned here.

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‫And whatever is positioned at the index one which is the second entry will be positioned here.

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‫So now we are going to replace zero this here with whatever the name value is and one with whatever

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‫the value is.

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‫Let's run this and see if this is going to work as well.

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‫And we see.

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‫Hello, my name is Alfonso.

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‫I'm 31 years old.

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‫So now for you is a little challenge.

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‫Create another variable up here, define one with a value assigned to it and use it inside of the string

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‫formatting real quick so you can use any value there.

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‫Okay.

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‫So I'm going to create another string.

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‫I'm going to call this one job and it will be developer.

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‫Like, So I'm so-and-so years old.

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‫I'm a developer or not a developer, but in curly brackets too.

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‫So now it's going to be indexed too.

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‫And I'm going to add the developer variable here.

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‫And actually it was called Java.

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‫So let me scroll out a little bit so we can see the entire line.

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‫So here it says, hello, my name is is zero.

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‫I am one years old and I am two.

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‫So these numbers are of course not the actual values, but they're going to be replaced with whatever

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‫we have here.

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‫So I hope you try this and you were successful at trying it.

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‫So here I'm adding another entry and it will say job.

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‫So let's see.

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‫Hello, my name is Alfonso.

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‫I'm 31 years old.

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‫I'm a developer.

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‫All right, so that worked great.

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‫Now let's look at string interpolation and I'm going to use it here.

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‫So this is the third concept of how you can manipulate your string, and that is called string interpolation.

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‫So string interpolation uses the dollar sign at the start, which will allow us to write our variables

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‫like this so directly used variable name instead of having to use indexes.

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‫So here I'm adding the Doppler at the beginning of the string.

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‫Hello, my name is then the name.

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‫I am a years old now you can leave name and aged up here at the end, but it's really not necessary

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‫at this point anymore.

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‫You can leave it out and you can run the code and you will see that it works the same way.

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‫So hello, my name is Alfonso and I'm 31 years old.

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‫So this is the more descriptive way where you don't have to use these indexes and you're never sure

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‫which variable was where.

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‫Well, that's not really the case, but still, it's a little more complex.

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‫I believe that this is a rather good way of doing it, where you don't have to use pluses all the time.

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‫And then we have a number four, which are verbatim strings.

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‫So let's look at those.

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‫So verbatim strings, we need to use the at and tell the compiler to take the string literally and ignore

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‫any spaces and escape characters like the backslash.

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‫N So let me show you what that means.

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‫So therefore I need to have a slightly bigger statement here.

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‫Let me add that in there like so, so now I have a super long string here and it has a lot of lower

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‫MIP some text.

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‫So what this will do is it will on one hand ignore any spaces and escape characters like backslash n,

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‫but at the same time, you see it takes the string literally.

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‫So wherever we have an empty space, let me add a couple in here, it's going to literally translate

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‫them.

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‫So here you see, I have two more spaces or not spaces, but entire lines that were added at this point.

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‫So that's what you can achieve by using this sign.

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‫If I were to use this backslash n by the way, for example, here in the string formatting, what this

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‫will do is it will create a new line.

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‫So here it says.

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‫Hello.

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‫My name is so here.

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‫You see there is this line break this backslash n creates a line break if you were wondering what this

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‫backslash n even means.

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‫And verbatim strings are very useful in specific cases.

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‫So let me show you.

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‫So here, instead of using backslash backslash to write file paths, we can use verbatim strings to

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‫make it easier.

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‫So if you remove the edge, you will get an error because backslash you backslash a backslash D are

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‫not valid escape characters, for example.

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‫So here you need to have this edit because otherwise it will think we're trying to escape something

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‫which means we're trying to use this backslash u as we've seen with the backslash n for example.

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‫Right?

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‫So here we used backslash.

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‫N Well I got rid of it, but here this backslash.

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‫N It would escape the character.

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‫N Meaning it doesn't consider this backslash.

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‫N as a character, but it just jumps to the next line or whatever.

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‫So what this would do in here is it will now give us this particular path and it will give us the dog

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‫photo.

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‫So that's where this ad sign is super useful.

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‫So whenever it comes to paths on your machine and then with verbatim strings, even valid escape characters

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‫won't work.

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‫So here, even this backslash n will not do anything.

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‫It doesn't have any powers in a verbatim string.

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‫So if we're using the ad sign here you can see more haha backslash and you have no powers here even

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‫though it does have power.

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‫So let me show you in another example.

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‫Without the ad.

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‫And now we have this backslash n.

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‫Then we will see more.

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‫Ha ha.

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‫Backslash.

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‫You have no power here, even though it should say you have powers here, for example.

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‫So let's run it again.

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‫And you see what?

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‫Ha ha.

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‫Backslash n you have no powers.

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‫That's why we're using the add sign.

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‫And here.

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‫Ha backslash n meaning line break.

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‫You have powers here.

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‫All right, so these are the different ways of string manipulation.

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‫And while for the first three, I would say it makes sense to decide for one of those and to use this

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‫consistently when it comes to verbatim strings, they really have special use cases, as you have seen,

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‫for example, with the location on your PC.

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‫So with the file path, for example.

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‫All right.

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‫So that's it for this video.

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‫See you in the next one.