问Powershell 7.2:转换-Json-日期处理

EN

- Hopefully, the proposal in the GitHub issue he links to, [#13598](https://github.com/PowerShell/PowerShell/issues/13598), will be implemented in the future, which would then simplify the solution to:

- This is achieved with a [`ForEach-Object`](https://learn.microsoft.com/powershell/module/microsoft.powershell.core/foreach-object) call that contains a helper script block that _recursively_ walks the object graph, which has the advantage that it  **works with JSON input whose timestamp strings may be** _**at any level of the hierarchy**_ (i.e. they may also be in properties of _nested_ objects).

- **Note**: The assumption is that the timestamp strings are only ever contained as _property values_ in the input; more work would be needed if you wanted to handle input JSON such as `'[ "2022-09-30T07:04:23.571+00:00" ]'` too, where the strings are input objects themselves.

# Sample JSON.
$val = '{ "date":"2022-09-30T07:04:23.571+00:00" }'

$val -replace '"(?=\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}\.\d{3}[+-]\d{2}:\d{2}")', "`"`0" |          #"
  ConvertFrom-Json |
  ForEach-Object {
    # Helper script block that walks the object graph
    $sb = {
      foreach ($o in $args[0]) { 
        if ($o -is [Array]) { # nested array -> recurse
          foreach ($el in $o) { & $sb $el } # recurse
        }
        elseif ($o -is [System.Management.Automation.PSCustomObject]) {
          foreach ($prop in $o.psobject.Properties) { 
            if ($prop.Value -is [Array]) {
              foreach ($o in $prop.Value) { & $sb $o } # nested array -> recurse
            }
            elseif ($prop.Value -is [System.Management.Automation.PSCustomObject]) { 
              & $sb $prop.Value # nested custom object -> recurse
            }
            elseif ($prop.Value -is [string] -and $prop.Value -match '^\0') { 
              $prop.Value = $prop.Value.Substring(1) # Remove the NUL again.
            }
          } 
        }
      }
    }
    # Call the helper script block with the input object.
    & $sb $_
    # Output the modified object.
    if ($_ -is [array]) {
      # Input object was array as a whole (implies use of -NoEnumerate), output as such.
      , $_ 
    } else {
      $_
    }
  } 

[string]$json = '{ "date":"2022-09-30T07:04:23.571+00:00", "key1": "value1" }'

[string]$jsonWithDatePrefix = $json -replace '"(\d+-\d+.\d+T\d+:\d+:\d+\.\d+\+\d+:\d+)"', '"#$1"'

[pscustomobject]$jsonWithDatePrefixAsObject = $jsonWithDatePrefix | ConvertFrom-Json

$jsonWithDatePrefixAsObject.key1 = "value2"

[string]$updatedJsonString = $jsonWithDatePrefixAsObject | ConvertTo-Json

[string]$updatedJsonStringWithoutPrefix = $updatedJsonString -replace '"(#)(\d+-\d+.\d+T\d+:\d+:\d+\.\d+\+\d+:\d+)"', '"$2"'

Write-Host $updatedJsonStringWithoutPrefix

$Data = ConvertFrom-Json $Json
$Data |Get-Node -Where { $_.Value -is [DateTime] } | ForEach-Object {
    $_.Value  = GetDate($_.Value) -Format 'yyyy-MM-ddTHH\:mm\:ss.fffzzz' -AsUTC
}
$Data

function ConvertFrom-Json {
    [CmdletBinding()][OutputType([Object[]])] param(
        [Parameter(ValueFromPipeLine = $True, Mandatory = $True)][String]$InputObject,
        [String]$DateFormat = 'yyyy-MM-ddTHH\:mm\:ss.fffffffzzz', # Default: ISO 8601, https://www.newtonsoft.com/json/help/html/datesinjson.htm
        [Switch]$AsLocalTime,
        [Switch]$AsOrdered
    )
    function GetObject($JObject) {
        switch ($JObject.GetType().Name) {
            'JValue' {
                switch ($JObject.Type) {
                    'Boolean'  { $JObject.Value }
                    'Integer'  { 0 + $JObject.Value }                                                 # https://github.com/PowerShell/PowerShell/issues/14264
                    'Date'     { Get-Date $JObject.Value -Format $DateFormat -AsUTC:(!$AsLocalTime) } # https://github.com/PowerShell/PowerShell/issues/13598
                    Default    { "$($JObject.Value)" }
                }
            }
            'JArray' {
                ,@( $JObject.ForEach{ GetObject $_ } )
            }
            'JObject' {
                $Properties = [Ordered]@{}
                $JObject.ForEach{ $Properties[$_.Name] = GetObject $_.Value }
                if ($AsOrdered) { $Properties } else { [PSCustomObject]$Properties }                  # https://github.com/PowerShell/PowerShell/pull/17405
            }
        }
    }
    GetObject ([Newtonsoft.Json.Linq.JObject]::Parse($InputObject))
}

ConvertFrom-Json $Json -DateFormat 'yyyy-MM-ddTHH\:mm\:ss.fffzzz' |ConvertTo-Json -Depth 9