ConvertTo-JSON from string - access JSON fields by name in PowerShell - json

Question

How can I access a field like $body.uuid?
This is what I have tried:
$body = #"
{ "uuid": "Test07",
"subject": "Template07-Subject",
}
"#
$bodyJSON = ConvertTo-Json $body
Write-Host $bodyJSON
Write-Host "uuid=$($bodyJSON.uuid)"
Write-Host "uuid=$($bodyJSON.$uuid)"
Results:
"{ \"uuid\": \"Test07\",\r\n \"subject\": \"Template07-Subject\",\r\n}"
uuid=
uuid=

Answer 1

Your $body variable contains a JSON string.
Unless your intent is to embed that string in another JSON string, do not call ConvertTo-Json on it - the latter's purpose is to convert objects to JSON strings.
In order to parse the JSON string into an object (graph), pass it to ConvertFrom-Json, which returns [pscustomobject] instance(s).
You can use regular property access, such as .uuid on the resulting object(s).
Note:
As bluuf points out, your original JSON contains an extraneous , after the "subject" property, which makes it technically malformed - this has been corrected below.
Note, however, that ConvertTo-Json in PowerShell (Core) 7+ still accepts such JSON, whereas Windows PowerShell does not.
# Create a string containing JSON
$body = #"
{
"uuid": "Test07",
"subject": "Template07-Subject"
}
"#
# Parse the JSON string into a PowerShell object (graph).
$bodyAsObject = ConvertFrom-Json $body
# Now you can use property access.
$bodyAsObject.uuid # -> 'Test07'