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Welcome back, round lesson nine, if else statements, so I showed you a little sneak peek of these

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in the last video, and you're actually going to be using these types of condition checks, lots and

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lots in JavaScript, and it's what's called control flow.

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So control flows when you're checking if one thing is true, then cool, execute one set of code.

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And if it's not true, then execute a different set of code.

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So you can use multiple checks, you can say if the is it just Cascade's like a waterfall, it's going

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to check this one.

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If that's false, it'll check that one.

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If that's false, it'll check that one.

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If that's false, it'll check everything else.

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Basically, it'll just go to the final set value so you can always set these up.

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So there is no code that gets run if you just choose to do an if statement or just if and else if that,

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it won't actually execute the else.

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But if you have the else in there, it will always execute this if everything else is false.

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OK, so the else is when it does not meet the condition else if is when you want to check for a second

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or third or fourth or etc condition.

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OK, so let's take a look and play with this.

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So let's just set an initial value here.

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Let's just do a pet name of Fido, OK?

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And let's give this mood.

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Let's give our Fido a mood of happy.

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Great.

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Fido was very happy.

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That is a permanent mood because we use the concept.

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So let's go ahead and check to see what the mood is.

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Is the mood exactly this string right here, these five characters in succession and nothing else?

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If so, then let's council log.

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Let's council log.

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That name

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is a

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mood.

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His pet name is totally a mood dog.

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You.

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All right, let's try that out.

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So if we just do the if by itself, then it's going to check it.

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If it's true, it'll execute this line of code so you can just use it if it's just by themselves, nothing

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else.

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Whatever you want to just say, make a certain line of code conditional, totally cool.

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And there are other ways to do that as well.

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OK, but what if we gave this and else condition the U.S., if that if this value up here wasn't true,

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then let's just say something else.

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Let's just say

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let's see.

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Will hopefully be happy soon.

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OK, so that's totally fine and obviously this is still true.

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But if we change this too sad or poor Drogo.

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Fido will hopefully be happy soon.

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Well, not with this constant one.

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Let's change that to a and maybe we can change it.

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Now, let's give this another value, let's give it a value of what is hungry, oops, is hungry, equal,

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true.

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OK, so this dog is hungry.

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Let's check if it's hungry.

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So it's just sometimes easier just to copy and paste or actually not not hungry as a as a string.

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Let's just all we have to check is he's hungry.

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Remember Truthy and falsey values.

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We don't have to do with truthiness obviously, because the value here is explicitly true.

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So if that is true, then console log.

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Let's say is hungry.

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OK, else will hopefully eat soon.

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OK.

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All right, so if it's not angry and hopefully it's harmless, you see?

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Fido's Hungaria.

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If you make that false.

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Hopefully to see so depending on the conditional expression, if this conditional expression is true,

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the one inside these parentheses, then it will execute this line of code.

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So is is Hungary true?

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No.

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Is Hungary is false.

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Is the mood happy?

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No, the mood is sad.

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OK, so if this doesn't trigger, then it will move on to the condition if one exists.

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Let's look at another example to let's to weight equals forty five.

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And let's do you know what this do to animals Fido's wait

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here and then let's do whiskers.

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We.

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It's the cat's whiskers, whiskers, and let's say, yeah, that's a good number, so we can use comparison

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operators like we had in one of the previous lessons to see if one is bigger than the other.

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So let's do Fido wait greater than.

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Keep that in is greater than Whiskas, wait.

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So if that's the case, then we can consider log.

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Fido weighs more,

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weighs more than whiskers.

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And then we could do else if then we could check for similar condition, but this time we're going to

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check for if they're exactly the same weight, OK?

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So if they have the same weight.

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Then to another value in say.

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They wear the same.

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Fido and Whiskers weigh the same amount,

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we see this fine and then we'll have an LST condition.

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So logically, if Fido doesn't weigh more than whiskers and they don't weigh the same, then what is

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the only possible other condition?

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The only other logical condition that that could happen, assuming obviously these both exist, which

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in our case they do, is that Whiskers weighs more than Fido.

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OK, so what if Fido lost a ton of weight and then Whiskers gained a ton of weight?

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If that were to happen, then whiskers would weigh more than Fido.

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If we change your values back then, Fido is more than whiskers.

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For some reason, we've got a real chunky whiskers.

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Then they would weigh the same.

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OK, so there you go, using comparison operators, if else, if and else to do comparisons and decide

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which line of code we want to.

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Well, we'll find out.

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It'll tell us, hey, this line of code is the one that's true.

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This line of code is the only one that's true, et cetera.

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OK, so that is, if else comparison operators and JavaScript control flow.

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And we're going to learn more about control flow with other ways of comparing between multiple things

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in another video.

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Thank you.