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Another option that we have for enumeration is what's

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referred to as the foreach numerator.

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So the first question would be what is a foreach enumerator?

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Well,

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the foreach statement is a scripting language construct for

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iterating through collections of items.

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You can then execute operations against each item that you found,

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and then you can process each item within the collection

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unless obviously you change the execution path.

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So what is in a for loop statement or a foreach loop statement?

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Well, the construct for each for loop statement is straightforward.

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It basically says foreach item in a collection, perform the specified task.

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So of course, the first thing in there is an item.

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So this is the variable that contains the current

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item that we're iterating through.

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The second is the collection that we're getting the items from.

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So you're going to say foreach item in the collection,

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the collection could be numbers, objects,

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files, etc.

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And then, of course, we have a script block,

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which is what happens when we've retrieved a specific item.

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So what does that look like in code?

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Well, the foreach base syntax is as simple as this.

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It's foreach (Item In Collection),

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so item in the collection is in the parentheses, so that's the evaluation.

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And then, of course, we have the script block,

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which is the code or the sequence of commands that need to execute.

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So if we create a variable here, which basically just has numbers 1 to 10,

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so it's effectively an array,

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I can then do a foreach statement and say foreach item, notice it's declared as

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a variable, so it's an inline variable, in the collection,

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which is the declared variable, and then,

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of course, I can write the value or perform some action on those values.

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Now, if we're looking at the syntax for this a little bit more,

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let's say we had three different types because,

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of course, when we're iterating through,

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it doesn't have to just be numbers.

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So I have collection1,

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which is numbers 1, 2, 3, 4, 5, all the way up to 10,

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collection2 is a series of letters,

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and then path equals the path to a specific file location.

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If we were to look at the number syntax,

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it would be similar to what we just looked at,

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so foreach item,

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as in each number in the collection, go and get that

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number and then write the value.

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If I was looking at the letters, the same principle would apply.

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So foreach item, the syntax doesn't change.

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You don't reference a different type of object

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unless you've declared it that way.

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But it basically just iterates.

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And then, of course, this time around, if we're looking at files,

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I can combine other things together.

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So I can say foreach file,

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remember that file and item are just arbitrary names for the variables.

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They only make sense when you call them later on.

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And then, of course, for this one,

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I want to use the path, but I can't just call path

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directly, so I have to use Get‑ChildItem,

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which is a regular out‑of‑the‑box PowerShell Command,

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which will then retrieve me an array object of all

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of the files in that directory.

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And then, at that point,

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I can just say Write‑Host Current Filename. So the foreach one is a common one.

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I use it a lot when we're iterating through various collections of data.

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It's nice and quick. It's easy to use.