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Welcome back to Learn to Code and JavaScript in this lecture, we are going to start talking about objects.

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Objects are just a way of grouping data together.

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So how do we define an object?

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An object is defined very similarly to how in arrays defined so we can group data together into one

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package and we use curly braces to define an object literal with commas separating the values.

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The difference between an object and an array.

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Is that the items in an object have a name.

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So this object has a name and age and a signed up attribute.

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So what my object equals, and you start with a curly brace name Colin, and of course, a string Bob

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comma, the next item, age column 12 comma, signed up colon.

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True.

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So that defines an object so the object owners can be accessed by their name.

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So I can say council that log my object, that name my object, that age.

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So I just can also be accessed using a string name with square brackets, kind of like an array, so

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I can say my object square bracket, string name, my object, square brackets, string age.

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So there's two ways to access the objects.

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There's also a null object.

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And you may have heard me refer to null.

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So that just means an object that has no value, that has nothing in it.

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Objects can store any type of data, including other objects, arrays and functions.

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When we get to functions, we'll look at that so I can say let my object equals name.

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Sue list an array.

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Twenty two.

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Forty four, sixty six, eighty eight.

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And then sub subject some other object.

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So let's take a look at some examples of how objects are built in visual studio code.

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All right.

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So let's build as an example, an employee object so we'll say what the equals.

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And if it's a longer name, we always put it on multiple lines.

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If it's a longer set of attributes in the object sequence.

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A name

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Bill.

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No, no, we use Kemel case on our names and of an object as well, and we'll say his employee number

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is one, two, three, four or five.

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I'm just going to be a strength,

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let's say, of four time.

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True.

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Salary for, say, ten thousand and then will create an array called shifts, which just represents

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the days and the week.

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So we'll start on Sunday.

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So we'll say Sunday, zero eight hours on Monday, eight hours on Tuesday, off on Wednesday, Thursday

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eight hours, Friday four hours and Saturday, four hours.

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And that's good enough for a quick example.

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So we'll leave it like that.

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And you need a semicolon at the end.

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And let's just log it out

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so we'll see what it looks like.

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So Output's, it's kind of like a race get output, we can have a little triangle and expand it so we

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know full time our name, see the sort of the attributes alphabetically and then our shifts, I can

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open those up and see what those are.

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And then let's just manipulate this a little bit.

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So then we'll say give Bill a raise.

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Saddam will say that salary.

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And so times equals one point of five dollars, going to get a five percent raise.

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So let's actually make those salary be an hourly salary.

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And so let's just make it ten dollars an hour.

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So now let's calculate bills, weekly pay.

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So we'll say let total pay equals zero and we'll say for S of we use the four of the loop and say that

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shifts

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and we will say total pay equals X times dot salary.

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And then we'll say cancel that log.

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Hey, Bill.

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Total pay.

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This is not define let us.

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So I paid off 40 to.

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And still looking out there on the bottom, so Bill gets paid for it, too, but let's say we've given

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Bill a raise.

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So Bill's salary is ten dollars and 50 cents after his raise.

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And then we calculate the pay.

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But let's say we were also going to cut Bill's hours.

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So say cut Bill's hours now we can't use an envelope to go through and subtract the hours we need,

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use a regular for loop, so we'll save for I equals zero.

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I was then and that shifts that the length.

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My post was.

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And then we'll say Abduh shifts, subi times equals are going to boy 10 percent cut point, not a 10

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percent cut in hours.

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So each one of these days is going to get cut by 10 percent.

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So now let's run this and see what we got.

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So now Bill is going to be paid thirty seven dollars and 80 cents and I realized an error early on,

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we should have been doing it plus equals here all along.

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So we've been underpaying poor Bill.

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So three hundred and two dollars and 40 cents, so if we go back and just cut that out, this cut just

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to see what that was.

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So previous three hundred thirty six dollars, so that's a brief introduction into defining and using

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objects.