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So let's go back into the PowerShell console again.

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We'll review the ForEach structure.

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And then, of course,

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we'll look at how we implement a ForEach enumerator within

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PowerShell using some kind of test data.

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Okay, so we just spoke about using a ForEach loop.

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And this, for me, is one of the most common loops that we would kind of use.

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So the first thing we're going to do is actually

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create a variable called collection, and we're going to do it this way, 4,

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5, 6, 7, 8, 9, and 10.

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And just to make sure that we have variables here and values, there we go,

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collection, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10.

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Now I could have done it using collection 1..10.

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It doesn't really make a difference.

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Now in order for us to loop through, we're going to use a ForEach command,

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which has the something in something, so the evaluation,

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and then it has the script block where we execute the commands.

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So the way this works, we first declare a variable.

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I'm going to call it item,

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or we could call it something that kind of makes sense,

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so I know it's going to be a number.

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So the name of that is really completely up to you.

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We then use what's called the in operator,

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and then we connect to the collection variable.

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And then, of course, we open our script block.

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I'm then going to say Write‑Host and just say Current Number,

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and then I'll just call my number variable here and close

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that out and then do this and then Enter.

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And then, of course, as you can see,

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it loops down through the numbers and says Current Number 1,

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2, 3, 4, 5, 6, 7, 8, 9, 10.

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So fairly straightforward to be able to loop.

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I mean that just looped through all of the numbers.

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Really, really simple.

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So let's just clear this again.

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Now let's say that we did the same thing again,

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collection, but this time we populated it using this approach, so 1..20.

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So same thing again.

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It's what's referred to as a range operator.

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So instead of declaring the actual numbers, we're just going to do a range.

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And then, of course, if we just go back through our code here,

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I can say ForEach number, write the number out,

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and then I'm going to enter that.

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And of course, the same thing happens again.

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So what's the difference between the two?

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Well, nothing,

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really because really what happens is when we create a collection of something,

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it doesn't have to be, you know, specifically in order.

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It could be something like this.

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So there's my collection, so I'm going to say collection.

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You'll see I have a list of numbers.

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And then when I want to create my loop,

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so let's go back to the ForEach, Write statement,

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close that one out, and then Enter, it'll just write the values.

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There's no specific thing here. It's not looking for an order of anything.

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So the range operator lets you kind of specify a start

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to an end, and it's a logical set.

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A collection could be anything again if they wanted to.

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Now, of course, we also have the ability, so let me just clear this out.

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We also have the ability to be able to use different words,

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letters, alphabet, whatever it would be, as part of that collection.

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So if we look here, I'm going to change my variable again.

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So we'll say collection equals, and then I'm going to

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populate it with letters instead, C,

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D, E, and F. We'll just do A, B, C, D, E, F. If I then say collection and

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render that, it will just give me the letters A, B,

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C, D, E, F.

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Now if we wanted to iterate through, we can repeat that same ForEach.

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Now I'm going to change it from number because it's going to be a letter,

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but my variable is still the same.

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What I'm then going to do is say Write‑Host The current letter

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is: $letter. Now notice, I can't tab this one because I

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haven't populated the variable yet.

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And then I'll do this and click Enter.

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And then it will say the current letter is A, B, C, D, E, F.

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So a standard ForEach loop can iterate through any kind of content really.

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It really makes no difference whether it's a number,

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whether it's a letter, whether it's a word.

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So if we were to change that even further,

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we could say $collection, and I could say Yes, No,

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Maybe.

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And when we look at the collection,

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It will always treat them as specific individual items.

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So the nice thing about the ForEach is that it doesn't really

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matter what we're trying to loop through and what we're trying

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to do with it. And any of the processing that we want to do, we

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can just run it against it.

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We don't need to strongly type anything.

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We can literally just say here's a bunch of text words, here's a bunch of

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letters, here's a bunch of numbers, here's a bunch of files,

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etc.

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So we have the flexibility of being able to iterate any kind of content by just using the ForEach statement..