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So let's go back into our PowerShell console,

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we'll review how to use the do/while and do/until loops,

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and then we'll look at how we implement those inside PowerShell.

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So let's talk about the do/while and the do/until kind of flows and what

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that looks like when we execute it here within PowerShell.

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So the first thing we'll do is actually create a variable

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called number and assign that with a number 1.

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So that's going to be our starting one.

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Now, to use the do/while, we're going to use the do command,

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and then, of course, we have our script block.

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Then, of course, we have our while command,

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and then we have our script block of anything that we need to do.

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So,

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what I'm going to do is I'm actually going to do each piece, so we'll

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say Do, and then we'll do our first one. Go down here.

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And the first thing I want to do is just render the

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number that will display the number to us.

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And then, of course, because we're using this kind of process,

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I can do number++, that will increment my number for me.

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I can then close out that do loop.

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Then I can say while, and then in regular brackets,

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remember we're not using the squirrely brackets here for this one,

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I can say number and then say is less than or equal to the number 10.

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So that gives me my loop process.

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So we can say do while so and so. So I'm going to press Enter now,

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and you'll see it iterates and then literally just stops at number 10

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because that was the comparison operator or the statement at the end

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that will say keep doing this while that one is less than specific 10

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number, or whatever that would be,

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whether it's greater than, less than, equal to, it

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doesn't really make a difference, but it runs at the end. Now what that means is,

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of course,

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is that it will keep iterating all the numbers here, and only once it's

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increased the number and then hits this line will it ever execute.

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Now what about if we change that and do a different statement?

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So we're going to do the Do Until loop. So, same thing again,

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we're going to do Do, switch statement, Until a specific thing.

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So let's just change my code again.

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So Do question, we'll do number so and so, then we'll increase the number again.

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So we'll say number++, we'll close that Do piece out, and

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then we'll say until the number is greater than 10, and then

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we'll do Enter. Now what happens?

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It basically runs until it gets bigger, and once it

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goes past the bigger, it just stops.

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Now, what would happen if we just clear that and redid our do statement here?

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So number, number here Do Until and changed it to have

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the same syntax which we had before,

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which was less than or equal to. How many times would it iterate?

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Well if we enter, notice it just keeps going and going,

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I'm going to stop that from running.

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So if we go back to our code for a second,

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you can see it says do it Until the number is less than or equal to that.

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And, of course, it just continues to iterate.

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Now, what is the value of number?

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Well if we go to number, it's 13290.

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So, of course, when you're building something like this,

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notice an important thing is to actually clear the values out.

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So every time I would want to run,

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I need to have a default value that I set this back to.

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So if we go to our Do number,

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number, and Until and then Enter that, it will stop at number 1.

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So just a little kind of side note there to be careful that

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when you're using loops of any description,

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whether it's a do/until or a do/while and you're

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repopulating or increasing a variable, if you need it to be reset,

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you need to somehow have a reset option; otherwise, the next time it's called it begins at the number where you left off.