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Kind of again in this list then we're going to talk about switch switches essentially another control

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flow command either helps us with organizing our nested if else statements.

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Let's see how we do that.

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The school had to exclude in school I'm going to close this.

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Start your project command line tool call it sewage project and then my switch project.

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The first thing I'm going to do I'm going to show you what is the problem you're trying to are to answer

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essentially using a switch statement.

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Imagine a situation like this.

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Imagine if you had an integer card my ends which is currently a value such as for.

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Of course as you know I'm putting a static ideas in here with in real life application.

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This idea would be fed to us from another resource.

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Now imagine I want to find the what is this likely one based on that do something.

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So if it is what I want to do something for this one.

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One other thing if this so on and so forth it would become something like this if my Int is zero then

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you do something else.

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If my end is one then obviously you do something else and then else if my end is I'm not to then the

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compiler had to turn something else.

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And as you can imagine this list of if else if else if I was keeping freezing depending on my situation

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why there's nothing wrong about coding like this there is a much better structure and that's called

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a switch.

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The switch works based on different cases and so you provide an expression that is your value and then

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you provided some cases and based on each case you decide about what you want to do.

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So let's come this into a switch statement.

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Let me first write a switch on the auto completion gives us some values in here.

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It shows us that for each unit to provide me an expression and then in the body of the switch you have

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to give me the case statements you want to run on break.

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So let's see how that actually works.

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I'm going to say the statement the expression that I want to switch is my in the case for it is if it

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was a 1 then and this log in it was one for instance then I'm going to say that's one case and then

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I have another case.

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And then in that case if case was to then say two and then break and then I'm going to say another case

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if it was three then right three and me read in then everything nice and tidy.

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So as you can see the writing of it is not necessarily shorter than writing it.

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If a state has a statement or an if else statement but it's a little bit more readable because you can

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see that in case it was one do this thing in case it was to do with the other things so on and so forth.

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And of course you need to have a default value that happens if none of them was actually valid actually

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going to add that the number say in the default say log on none of the above.

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None of them was actually correct.

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So that's essentially the structure of a switch is not very difficult.

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And you know once you get used to it you can use it for situations when your if else statement has multiple

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different situations.

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So you will need if else if and for that I would suggest that you use switch and other thing that I

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want to mention that is in it you can actually combine some of your cases.

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So for instance if you need a case of one and two to be considered the same you can actually do this

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you can say case one case two it is or it was one or two.

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So right now most of these cases they refer to this part of the court.

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And then of course there's a break after it which means you get out of the switch because of this system

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where the case gets compiled and calculate that.

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And that break happens after it switches off often more efficient than using an if else statement.

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If you have reach millions of entries or if else with millions of entries then switch would work a little

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bit faster in saying that that's really left up to your judgment depending on what you're doing and

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whether you feel like you know if is a better choice for there.

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It's an easier quote to right.

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Or whether a switch would be a better option.

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Now one viewer here I should mention something that switches often constrained that we use to be used

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with numerical values.

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For instance if an if statement you could do something like this in if else you could say if I don't

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know all my name is equal to a string by name.

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Exactly.

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Then to do something which means in the IF expression we are actually comparing two values of the type

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in a string.

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Unfortunately this switch doesn't provide much infrastructure.

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You cannot do something like this you cannot say switch.

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And then you need say a string and then for the cases how the strings again because switch doesn't accept

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and as a string as a value.

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So something you could do in here is this which is not really a very you know modern way of doing it

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but they found out that sometimes they actually help me.

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And here is how I would do it.

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Imagine I have a string and that this thing has to be compare it against the names.

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Vancouver San Francisco New York.

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And I don't know maybe.

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The other is Paris for instance.

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So if I have to compare against this I put all of these within an array.

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So I'm going to go ahead and say and this array or the strings array that is in this array and that's

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all right.

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I can't initialize with objects the objects aren't going to be in Vancouver and the other object is

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going to be this code.

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If that's how you type it I always have difficulty typing some something something I'm really good at.

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And some others are in New York and then Paris.

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OK.

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So that's about that.

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I need one more practice of course.

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Give me a stack of them so we can see them nice and neat and proper So now we want to switch a certain

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value.

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Imagine my value as a string.

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My strength is going to be let's say you are.

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So we want to know if money is streambed is indoors.

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We want to find out.

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We want to use a switch for that if as statement here is something you could do.

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You could say switch in the switch.

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You need to provide an integer.

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So I'm going to say integer my code is my integer let's call it city index.

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That's going to be s t r array index of objects.

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My A C R.

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So I'm saying go to these things array and find what is the Index of this guy.

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What's that index of New York in here.

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So it's going to go 0 1 2 and he's going to find two.

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So I'm going to say switch city index and then chase zero.

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If it was under zero then I'd say this like it was first for instance or whatever that you wanted to

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do for you another case would be case 1 for instance.

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And yet I'm to say it was soccer and so on and so forth.

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The only warning we have in here and I think we have seen this in the past that this is an integer.

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This is a long unsigned.

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So I'm going to say Forsett cast it into an integer.

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So this would be another way for switching between a string ralliers of course is another very very

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common practice.

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But you know if you were wondering is it at all possible to switch string.

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Yes you can pull all of your values inside an array and find the index of your object the one you're

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searching for in there.

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And as a result you can actually use it.

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So it is kind of a trick because simply again switches using an integer but kind of gets the work done.

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So I'd be happy with that.

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So a quick recap of everything switches used in a sort of a nested series of if else statements switch

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can switch different values expressions and for each of them it provides a case for each of the cases

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you decide about what is going to happen and you'll break out of your switch and you can combine different

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cases.

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That's about that.

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And I shall see you guys in the next lesson.