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One of the great things I love about PowerShell is,

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in fact, that I work with objects in the pipeline,

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and this is something that you want to keep in the back

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of your head, always be thinking,

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how am I going to take advantage of this object?

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What can I do with it?

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How can I do more with it?

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And one of those things that I think you'll use often is you

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can create custom properties that you need.

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You don't have to rely on the default output that a command gives you.

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If you need something else, you can probably create it,

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and it's really not that difficult.

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You can do it all from a prompt.

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You don't have to be a developer in order to extend PowerShell.

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In fact,

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you can create custom objects right from the PowerShell

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prompt that you can then use in the PowerShell pipeline to

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do other things that you want.

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I love this idea about PowerShell being a tool that I can make

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work the way that I need it to get my job done.

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I'm not relying necessarily on someone else to do that.

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For example, if I want to create a custom property,

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and I'm going to have some demonstrations here in a moment,

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we'll go into this in much more detail, but let me give you an example here.

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One way to create custom properties is with Select‑Object.

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In my example here, I'm giving all of the files under the data directory,

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and then I'm selecting some key properties,

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so we've already seen Select‑Object, so I'm saying,

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hey, give me the Fullname, the Name, and the LastWriteTime.

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After that part, some custom properties,

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and the custom properties are defined with a hash table,

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and we've talked about hash tables earlier in the course.

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So the hash table that you use to create a custom

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property has two predefined keys, Name and Expression.

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The Name will be the Name of the custom property,

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so I'm creating a custom property called Size,

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and the Expression value will be a script block,

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and we looked at script blocks also earlier in the course.

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The script block will execute once, in this case,

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for every object in the pipeline, and that's what $_ is showing.

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So the Size property will have a value of the Length

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property of every file object in the pipeline.

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The Computername property will have a value of the environmental variable,

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computername.

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Now, here's really the fun part.

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I can create something out of thin air, so I'm going to create,

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because the purpose of my little command here is I want to

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basically create a little audit trail and say,

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what's the status of the files on a particular date,

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so I'm going to create a new property called Audit,

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and the value of that property will be Get‑Date,

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and I'm formatting it as a string because this is all

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going to be exported to a CSV file anyway.

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PowerShell and the ability to create a custom property allows me to get

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more information that's relevant to what I want to do.

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And by the way, when I use these things with Select‑Object,

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this is also going to create a custom object,

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although here's another way that you can create a custom object.

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So I'm going to run Get‑Process and Get‑Service and

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save those things to our variables.

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Now, I'm creating a hash table,

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$h, and in $h, the keys and values will become an object, and the

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way that I create that object, this is one way, is using the new

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object cmdlet, use the PSObject TypeName, and then the property

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can just be that hash table.

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Any hash table I can turn into an actual PowerShell object, just like that.

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When I get to the demonstration, I'll also show you how to use the pscustomobject shortcut.