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This lesson, we're going to be looking at our options when we're doing logical operators, where we've

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got an option to include more than one condition to check, to see if they are true.

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And we also have some flexibility there where we can check to see if both are true and then both need

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to be true in order to equate to being true.

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Otherwise, it's false, which allows us to check to see if either one of them is true.

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And then we've got logical not which returns false.

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If a single operand can be converted to true and otherwise it returns true.

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So there's more information on this at the Mozilla Developer Network.

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They've got some great examples here within the expressions logical operator demo.

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So we see that we've got a value of A is set to three, B is set to negative two.

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So the condition is checking to see if A is greater than zero.

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And for the first one that's going to equate to being true.

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But for the second one, that's going to be false.

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So that's why we've got an expected output of false.

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If we use the word statement and we use the same conditions, we see that this one is true, this one

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is false.

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So that means that we're getting true returned.

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And then we've got the where we've put the exclamation mark where we're negating that.

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So because this statement, as we saw over here, is coming out as true, it's negating it.

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It's turning it, flipping at the opposite.

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So that's why we're being returned back as false.

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So there's some great examples here and there's some more explanation about how you can utilize these

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within your code as well.

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So we do have an exercise challenge for this lesson where we're going to ask the users an age via prompt

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and check to see if their age is over 18.

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And if they are, then we're going to show the message to allow or deny if they are less than 18 and

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we're going to use a ternary operator for that.

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And then also checking to see if a user is a member.

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So it's going to be a boolean value that the user is a member and then we're going to output a message

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to them if they are or if they're not allowing entry to that.

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And here's a sneak peek at the code so you can go ahead and pause the video and write out this challenge

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and I'll walk you through the solution coming up.

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So first thing that we want it to do is capture the user age.

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So we set up a variable, declare a variable for that.

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And we're going to do that all within one statement where we've got the prompt and that's going to capture

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the user's response into the user age value variable.

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And you can also output that into the console as well.

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So you can just make sure that you've captured it.

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We want to convert that into a number.

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So if it looks like a number of JavaScript is already going to try to convert it into a number if we

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try to use it as a number, but just in case.

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So is a good idea to force it and do the conversion type into a number, then we do our check.

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So we're going to create a message using the territory operator and that user age value.

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And we're checking to see if the age is greater than or equal to 17.

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And if it is, then we're going to ask and we're going to do a cloud.

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So our message is going to be allow and we can console log out the results of the message as well in

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the console.

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So try that one and refresh.

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So we ask an age and we see that the age comes back as 20.

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So we're allowing that age to come through using the territory operator.

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And the second part of the challenge was to take our user age and to check to see if they're greater

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than seventeen and also if they are user member.

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So if this is true, then we can output a message to the console that, yes, allow otherwise its output

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of the console.

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Nope.

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And we're going to do one more value here for the user member.

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So first off, we can set user member to be true.

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So if all of these conditions are met, we're going to get.

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Yes, allow if the person's age is under, we're going to get Dinni and no Denyer so we can add in even

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more complex.

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And then member can come back here and we can see that there is a value for member or we can check to

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see if member is equal to particular value.

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It's always good to wrap this with the round brackets so it's more readable, but you don't have to

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for the code to work so that we can see that whatever age we enter in here, that we allow it because

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the value of member is Lowrance.

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So if the value of member is something else, just got in a quick five there.

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So even though we get 20, we're not going to be allowed.

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So we're allowed to enter because we are of an age, but we don't get entry because we're not a member

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within the membership list.

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And coming up next, I'm going to have another we're going to have another challenge for you.

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So let's come in in the next lesson.