How to iterate through a unknown JSON data/object? - json

Question

Given the two JSON examples
{
"A": {
"name": "noname",
"key": "nokey"
}
and then
{
"B": {
"property1": "value3",
"country": "australia"
}
}
Is it possible to create a Powershell script that could take either one of the JSON examples and loop through them without knowing any names/keys upfront? (Using Windows 2016)
Something similar to what is posted as an answer here How do I loop through or enumerate a JavaScript object?
var p = {
"p1": "value1",
"p2": "value2",
"p3": "value3"
};
for (var key in p) {
if (p.hasOwnProperty(key)) {
console.log(key + " -> " + p[key]);
}
}
Not working
Did try this, but it works only for the first level
$json = #"
{"A": {"property1": "value1", "property2": "value2"}, "B": {"property1":
"value3", "property2": "value4"}}
"#
$parsed = $json | ConvertFrom-Json
$parsed.PSObject.Properties | ForEach-Object {
$next = $_
$name = $_.Name
$value = $_.value
echo "$name = $value"
$next.PSObject.Properties | ForEach-Object {
$name = $_.Name
$value = $_.value
echo "Second level: $name = $value"
}
}

Answer 1

ConvertFrom-Json uses a nested structure of PSCustomObjects to represent the data - you can use $x.psobject.properties to get a collection of json property names and values for each item in the structure, and then you can loop over them however you want.
For example:
$x = ConvertFrom-Json "{ 'A': {'name': 'noname', 'key': 'nokey'} }"
foreach( $rootProperty in #($x.psobject.properties | where-object {$_.MemberType -eq "NoteProperty"}) )
{
write-host "'$($rootProperty.Name)' = '$($rootProperty.Value)'"
foreach( $childProperty in #($rootProperty.Value.psobject.properties | where-object {$_.MemberType -eq "NoteProperty"}) )
{
write-host "'$($childProperty.Name)' = '$($childProperty.Value)'"
}
}
outputs the following:
'A' = '#{name=noname; key=nokey}'
'name' = 'noname'
'key' = 'nokey'
You could also walk the structure recursively to an arbitrary depth if you convert the above into a function that calls itself on nested PSCustomObjects, but I'm not sure if you need to be able to do that or just go 2 levels like in your example json documents.