Create Hashtable from JSON - json

Question

I want to get a JSON representation of a Hashtable such as this:
#{Path="C:\temp"; Filter="*.js"}
ConvertTo-Json results in:
{
"Path": "C:\\temp",
"Filter": "*.js"
}
However, if you convert that JSON string back with ConvertFrom-Json you don't get a HashTable but a PSCustomObject.
So how can one reliably serialize the above Hashmap?

Answer 1

$json = #{Path="C:\temp"; Filter="*.js"} | ConvertTo-Json
$hashtable = #{}
(ConvertFrom-Json $json).psobject.properties | Foreach { $hashtable[$_.Name] = $_.Value }
Adapted from PSCustomObject to Hashtable

Answer 2

A little late to the discussion here, but in PowerShell 6 (Core) there is a -AsHashtable parameter in ConvertFrom-Json.

Answer 3

JavaScriptSerializer is available since .NET3.5 (may be installed on XP, included in Win7 and newer), it's several times faster than Convert-FromJSON and it properly parses nested objects, arrays etc.
function Parse-JsonFile([string]$file) {
$text = [IO.File]::ReadAllText($file)
$parser = New-Object Web.Script.Serialization.JavaScriptSerializer
$parser.MaxJsonLength = $text.length
Write-Output -NoEnumerate $parser.DeserializeObject($text)
}

Answer 4

The answer for this post is a great start, but is a bit naive when you start getting more complex json representations.
The code below will parse nested json arrays and json objects.
[CmdletBinding]
function Get-FromJson
{
param(
[Parameter(Mandatory=$true, Position=1)]
[string]$Path
)
function Get-Value {
param( $value )
$result = $null
if ( $value -is [System.Management.Automation.PSCustomObject] )
{
Write-Verbose "Get-Value: value is PSCustomObject"
$result = #{}
$value.psobject.properties | ForEach-Object {
$result[$_.Name] = Get-Value -value $_.Value
}
}
elseif ($value -is [System.Object[]])
{
$list = New-Object System.Collections.ArrayList
Write-Verbose "Get-Value: value is Array"
$value | ForEach-Object {
$list.Add((Get-Value -value $_)) | Out-Null
}
$result = $list
}
else
{
Write-Verbose "Get-Value: value is type: $($value.GetType())"
$result = $value
}
return $result
}
if (Test-Path $Path)
{
$json = Get-Content $Path -Raw
}
else
{
$json = '{}'
}
$hashtable = Get-Value -value (ConvertFrom-Json $json)
return $hashtable
}

Answer 5

I believe the solution presented in Converting JSON to a hashtable is closer to the PowerShell 6.0 implementation of ConvertFrom-Json
I tried with several JSON sources and I always got the right hashtable.
$mappings = #{
Letters = (
"A",
"B")
Numbers = (
"1",
"2",
"3")
Yes = 1
False = "0"
}
# TO JSON
$jsonMappings = $mappings | ConvertTo-JSON
$jsonMappings
# Back to hashtable
# In PowerShell 6.0 would be:
# | ConvertFrom-Json -AsHashtable
$jsonMappings | ConvertFrom-Json -As hashtable

Answer 6

you can write a function convert psobject to hashtable.
I wrote a answer here:enter link description here