A dictionary inside of a dictionary in PowerShell - powershell

Question

So, I'm rather new to PowerShell and just can't figure out how to use the arrays/lists/hashtables. I basically want to do the following portrayed by Python:
entries = {
'one' : {
'id': '1',
'text': 'ok'
},
'two' : {
'id': '2',
'text': 'no'
}
}
for entry in entries:
print(entries[entry]['id'])
Output:
1
2
But how does this work in PowerShell? I've tried the following:
$entries = #{
one = #{
id = "1";
text = "ok"
};
two = #{
id = "2";
text = "no"
}
}
And now I can't figure out how to access the information.
foreach ($entry in $entries) {
Write-Host $entries[$entry]['id']
}
=> Error

Answer 1

PowerShell prevents implicit iteration over dictionaries to avoid accidental "unrolling".
You can work around this and loop through the contained key-value pairs by calling GetEnumerator() explicitly:
foreach($kvp in $entries.GetEnumerator()){
Write-Host $kvp.Value['id']
}
For something closer to the python example, you can also extract the key values and iterate over those:
foreach($key in $entries.get_Keys()){
Write-Host $entries[$key]['id']
}
Note: You'll find that iterating over $entries.Keys works too, but I strongly recommend never using that, because PowerShell resolves dictionary keys via property access, so you'll get unexpected behavior if the dictionary contains an entry with the key "Keys":
$entries = #{
Keys = 'a','b'
a = 'discoverable'
b = 'also discoverable'
c = 'you will never find me'
}
foreach($key in $entries.Keys){ # suddenly resolves to just `'a', 'b'`
Write-Host $entries[$key]
}
You'll see only the output:
discoverable
also discoverable
Not the Keys or c entries

Answer 2

To complement Mathias R. Jessen's helpful answer with a more concise alternative that takes advantage of member-access enumeration:
# Implicitly loops over all entry values and from each
# gets the 'Id' entry value from the nested hashtable.
$entries.Values.Id # -> 2, 1
Note: As with .Keys vs. .get_Keys(), you may choose to routinely use .get_Values() instead of .Values to avoid problems with keys literally named Values.