Filer json by selecting a particular node - powershell-4.0

Question

I am having my JSON as follows
{
"Root": [{
"Child": [{
"Id": "1"
}],
"Child1": [{
"Id": "2"
}]
}]
}
I am getting the content as follows
$content = (Get-Content -filepath) -join "`n" | ConvertFrom-Json
What I need is If I pass from the script as Child1 I need to extract the following node and show
"Child1": [{
"Id": "2"
}]

Answer 1

Since you're using PS3+, instead of joining the lines (it's slow), read the file as one string via -Raw:
$content = Get-Content $filepath -Raw | ConvertFrom-Json
Filtering by name, showing contents without name:
$name = 'Child1'
$content.Root.$name | ConvertTo-Json
In PS2.0:
$content.Root | Select -expand $name | ConvertTo-Json
Filtering by name, showing name and contents:
$name = 'Child1'
($content.Root | select $name | ConvertTo-Json) -replace '^.|.$',''
Filtering by Id, showing contents:
$content.Root | ForEach { $_.PSObject.Properties.Value | Where Id -eq 2 } |
ConvertTo-Json
Filtering by Id, showing name and contents of the node:
($content.Root |
ForEach {
$_.PSObject.Properties |
Where { $_.Value.Id -eq 2 } |
ForEach { #{$_.Name = $_.Value} }
} | ConvertTo-Json
) -replace '^.|.$',''