I started writing about PowerShell in June 2014 at tommymaynard.com. While I’m not a Microsoft MVP, I’m certainly working to obtain Microsoft’s longevity award. While the distinction doesn’t actually exist, this year will mark six consistent years of reading, researching, spending my time with PowerShell, and giving back to the community in my written word. With the combination of my site and this one, I’ve authored somewhere close to 350+ articles, or posts.
What I’m really out to say here, is that in my time, I’ve noticed which of my writings have been consistently popular. There’s a particular post on my site that sees the largest amount of consistent visitors: It’s Hash Table to CSV. I’ve been looking for a way to take its personal success and provide more to the reader about the topic. That’s what we’re doing today with this post. I put a link to the original post on Twitter recently, and someone provided me an idea for an update — whether they realized it or not. It’s simple, but whatever. As proven, those are sometimes the most popular posts.
Before we get back into this, let’s remember how this all started. It started here: Hash Table to CSV. It’s always been a popular post, but just in case you didn’t follow this over from PowerShell.org, then you need to know this is a forward movement on that 2018 article.
I was sitting around and wondered how to best get a hash table into a CSV file. Maybe it was for configuration; I still don’t recall. Well, my option wasn’t the only option, and so today I’ll pass along something someone on Twitter pointed out that I hadn’t considered myself. We can use [PSCustomObject], introduced in (Windows) PowerShell 3.0.
I’ve long used this to create custom objects for its speed and insertion order preservation (over New-Object), but it didn’t occur to make use of it when getting a hash table into a CSV. It does work, with less work, so let’s try it on. While I won’t show the previous option, revisit the first article on this topic to see the old way; here’s the new way. We’ll start with our previously used hash table.
$HashTable = @{
Name = 'Tommy'
StreetName = 'Vista Pl.'
City = 'Tucson'
}
$HashTable
Name Value
---- -----
Name Tommy
StreetName Vista Pl.
City Tucson
Once that’s populated, instead of using the hash table’s GetEnumerator method, we’ll use [PSCustomObject]. This converts each entry in our hash table into an object, and sends the object to the Export-Csv cmdlet. We get what we expect in our CSV file without the additional work scripted into the first hash table to CSV article from 2018.
[PSCustomObject]$HashTable |
Export-Csv -NoTypeInformation -Path .\Desktop\NewHashToCsv.csv
And, that was it. Quicker, easier, and more likely to be remembered, long term.
Edit: It was pointed out to me that this didn’t produce the exact information in the CSV from 2018. Instead of having a Key and Value properties, it included a property/column for each of the hash table’s keys: Name, StreetName, and City. Honestly, I think I like this better, as it reminds me of what any command that returns objects in PowerShell would do for us. If I were to read it back into the host (via Import-Csv), my output from the operation would be more in line with what PowerShell commands produces anyway: objects with properties. Thank you for the observation, Mike!
