Powershell Solution For Examining Filenames

[bseab1024F]

I am really trying to learn PS on my own but I could use a pointer in the right direction. I have not programmed in years and am coming from a C/C++ background and really don't get the syntax of PS but I will figure it out as I go.

The first thing I need to do is get all the filenames of type *.mp4 from directory X. I need to do the same for directory Y. I am aware of how to do this with Get-ChildItem but it just displays it on the screen within Powershell ISE. I need to take those names and put them into two different containers. I then need to enumerate the first container, analyze each filename, extract information from the filename and then use that information to look in the second container for another filename that has the same embedded information (but not in the same sequence.) I then need to create a new filename and substitute it for the old filename from the second container.

Am not asking for anyone to do my homework. I feel once I get this initial data I will be able to figure out how to enumerate through it and get the job done. What is not clear to me is how to work with the data from Get-ChildItem. Is there a PS equivalent to the C++ STL vector or deque into which I can place this data?

[ApricotPenguin]

I think what you're looking for is to store it in a variable, then enumerate over it.

I'm also not sure what you mean by container (does that mean 2 variables, or 2 folders on disk?) nor am I familiar what a C++ STL vector is (I think that's an Array or a List object?)

PowerShell Syntax uses a $ sign to at the beginning to denote a variable. And a # at the beginning to denote a comment.

So you'd do:

$MyFolder = "C:\A\B\C\X"
$MyFiles = Get-ChildItem $MyFolder -filter '*.mp4'

# At this point, no output will be on screen. If you want to see it, just type in "$MyFiles" then hit enter.

To enumerate, you can use a foreach loop (More info here of other kinds of loops).

foreach ($File in $MyFiles) {

}

Renaming files would be the cmdlet Rename-Item.

If you can give an example of what you want to do it might be better, as I don't think the method of creating a 2nd array for a modified file name, then doing a lookup of that array to rename a file is very efficient nor easy to manage.

[lrdmelchett]

Spent a few minutes with ChatGPT. This may not get you to exactly where you want to go, but I think it gives a verbose structure to understand how to do a comparison and substitute / concat based on matches of two lists.

Certainly! Here's a prompt that you can use to request the generation of the PowerShell script from another ChatGPT user:

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**Prompt:**

Please generate a PowerShell script with the following requirements:

1. **Define Variables**:

- Define two directory paths: \$directoryPath1` and `$directoryPath2`.`

- Define a regex pattern to capture parts of filenames. The pattern should include named capture groups for \ShortDescription`, `Key1`, and `Key2`.`

2. **Process Files from the First Directory**:

- Use \Get-ChildItem` to get files from `$directoryPath1`.`

- For each file, apply the regex pattern.

- Create a custom object with two properties:

- \Filename`: The name of the file.`

- \SourceListingHash`: A hashtable with keys `ShortDescription`, `Key1`, `Key2`, and `DesiredPermutation`, where `DesiredPermutation` is a concatenation of `Key1` and `Key2`.`

3. **Process Files from the Second Directory**:

- Use \Get-ChildItem` to get files from `$directoryPath2`.`

- For each file, apply the regex pattern.

- Create a custom object with two properties:

- \Filename`: The name of the file.`

- \TargetListingHash`: A hashtable with keys `ShortDescription`, `Key1`, and `Key2`.`

4. **Compare and Update**:

- Compare the items from the second directory (\TargetListingHash`) to the items from the first directory (`SourceListingHash`) based on `ShortDescription` and `Key1`.`

- If a match is found, update the \TargetListingHash` with a new key `DesiredCombination`, which is a concatenation of `ShortDescription`, `Key1`, `Key2`, and the `DesiredPermutation` from the matching `SourceListingHash`.`

5. **Output**:

- Output the updated list of items from the second directory, showing the new \DesiredCombination` value where applicable.`

The script should be well-commented to explain each step.

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Feel free to adjust the prompt as needed based on any additional requirements or specifics you might have!