Sort Hashtable with Arrays as values


Description: I’m building a PowerShell-script that searches for files, then gives them unique names, copies them and then verifies them via hash-calculation – I chose to split the script in functions for each step, so it’s easier to maintain the whole thing.
To get all values from one function to the other, I chose to use [hashtable]$FooBar – inside $FooBar, there are multiple arrays, such as FullName or OutputPath (which may change per file as they will be copied to subfolders named yyyy-mm-dd). All arrays are correlating with each other (meaning that index 1 contains all values of the first file, index 2 the values for the second file,…) and this works fine as of now.

A short simplified visualisation:

However, I now need to sort them all by one value-set of one of the arrays, e.g. the size. Or, visualised again:

I tried $FooBar.GetEnumerator() | Sort-Object -Property Size, but this does not change anything. Google turned up suggestions on how to sort an array of hashtables, but in my case, it’s the other way round, and I can’t get my head around this because I don’t even understand why this is a problem in the first place.

So my question is: is there any way to sort all arrays inside the hashtable by the value-set of one of the arrays? I can’t get my head around this.

Disclaimer: I’m a PowerShell-autodidact with no reasonable background in scripting/programming, so it might well be that my “include everything in one hashtable”-solution isn’t going to work at all or might be extremely inefficient – if so, please tell me.


The easiest way to go about what I believe you are trying to do is Select-Object

This will create an array of new objects that only have the desired properties. The reason this works and your method doesn’t is because Sort-Object works on properties and the property you are specifying is behind a few layers.

If you need more flexibility than just exact properties, you can create your own like this

Or manually create new properties with the [PSCustomObject] type accelerator:


If you need to add additional properties to the object after it’s initially created you have a few options.


The most common method by far is by using the Add-Member cmdlet.

Something important to keep in mind is that by default this cmdlet does not return anything. So if you place the above statement at the end of a function and do not separately return the object, your function won’t return anything. Make sure you either use the -PassThru parameter (this is also useful for chaining Add-Member commands) or call the variable afterwards (like the example above)


You can select all previous properties when using calculated properties to add members. Keep in mind, because of how Select-Object works, all methods from the source object will not be carried over.


This one is my personal favorite, but it’s restricted to later versions of PowerShell and I haven’t actually seen it used by anyone else yet.

Each member type has it’s own constructor. You can also add methods to $fooBar.psobject.Methods or either type to $fooBar.psobject.Members. I like this method because it feels more explicit, and something about adding members with members feels right.


The method you choose is mostly preference. I would recommend Add-Member if possible because it’s the most used, therefore has better readability and more people who can answer questions about it.

I would also like to mention that it’s usually best to avoid adding additional members if at all possible. A function’s return value should ideally have a reliable form. If someone is using your function and they have to guess when a property or method will exist on your object it becomes very difficult to debug. Obviously this isn’t a hard and fast rule, but if you need to add a member you should at least consider if it would be better to refactor instead.


Sort Hashtable with Arrays as values by licensed under CC BY-SA | With most appropriate answer!

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