Rokett's musings

Iterating over a PowerShell hashtable….it’s not as easy as a simple ForEach loop; a hashtable isn’t like an array.

So how do you iterate over a hashtable? It’s actually really easy as there is a method on the hashtable object called GetEnumerator(). Iterating a hashtable using the GetEnumerator() method sends each key/value pair to the pipeline.

$hashtable = @{
    'key1' = 'value1'
    'key2' = 'value2'
    'key3' = 'value3'
}

$hashtable.GetEnumerator() | ForEach-Object {
    Write-Host "$_.Key : $_.Value"
}

or if you prefer a ForEach loop instead of the pipeline (see https://rokett.github.io/post/powershell-performance-and-foreach-loops/)

$hashtable = @{
    'key1' = 'value1'
    'key2' = 'value2'
    'key3' = 'value3'
}

$hashtable2 = $hashtable.GetEnumerator()

ForEach ($item in $hashtable2) {
    Write-Host "$($item.Key) : $($item.Value)"
}

The above code will output the following:

key3 : value3
key1 : value1
key2 : value2

Or something similar; iterating over a hashtable does not necessarily do it in the same order that it was created.