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So let me give you some basics on working with script blocks.

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Now in this module, all of my code samples are going to be in the slides,

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I'm not really going to be any live demo because it's just

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as easy to see them on the screen here,

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but the course downloads does have all of the code that I'm showing you,

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so you can download that, grab the code,

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open it up in your editor, and try these things out for yourself.

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So I'm going to create a script block and I'm going

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to save this to a variable $sb.

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In the script block,

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we're going to have a set of curly braces and whatever code that you want

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to run in the script block goes inside the curly braces.

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Inside the curly braces, you can have a single line of code as I have here,

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you can have multiple lines of code,

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just hit Enter after each line and then just make sure

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you close your closing curly brace.

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PowerShell will figure out what is inside your

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script block and know how to run it.

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You can have as much code as you want inside those outer curly braces.

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If it's a single line like I have here, you really don't have to do anything.

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If you have multiple lines of code,

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just hit Enter after every line and then PowerShell will figure

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it out when you try to use that script block.

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To run the script block like that one I just created,

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you can use the invoke operator which is the ampersand here,

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so I can just tell PowerShell ampersand,

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meaning run or invoke, the variable $sb because that's a script block,

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PowerShell knows what to do.

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So the script block runs and I get the results.

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The output of the script block is the same as if I had

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manually run the code within the script block.

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The difference is the script block made it a whole

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lot easier for me to run that code.

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If I decided later in the day I want to get the same data again,

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all I have to do is rerun that really short script block variable,

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I don't have to try to rerun all the code that is inside the

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script block that I created originally.

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This obviously makes PowerShell really easy to reuse.

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The other way that you can invoke a script block is to use Invoke‑Command.

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Invoke‑Command, if you looked at the help,

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you'll see has a script block parameter which is positional,

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so I can just do Invoke‑Command or the alias icm and

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give it the name of my variable, which has a script block,

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and PowerShell will do its thing,

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and I'll get the same result as I just showed you.

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You'll also find Invoke‑Command very useful when you go to

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PowerShell remoting because I'll be able to run that script block

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remotely on one or more multiple computers.

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So as I said earlier,

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script blocks are everywhere in PowerShell used all the time,

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you've seen them, you may not have known what they were called.

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So Get‑Process, piping it to Where‑Object.

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Where‑Object is using a filtering script block so that code within this

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curly braces where $_.ws is greater equal to 100 MB,

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PowerShell evaluates or runs that code, filters the process objects,

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and then I can pipe them to select object and there are the results.

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Here is another example.

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I am first defining a hashtable called $new and this will be

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parameters that are part of the new item cmdlet which is

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going to be in my foreach object.

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So I'm going to take the numbers 1 through 10,

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and for each 1 of those numbers,

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I'm going to create a new directory called Data‑1‑2‑3 and

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so on and I'm splatting the hashtable.

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So for each object is using a script block,

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so you have the curly brace New‑Item code closing curly brace.

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Don't confuse the hashtable that I've defined with $new with a script block. The hashtable has the @ symbol in front of it, the script block does not.