PowerShell : retrieve JSON object by field value

问题:

Consider JSON in this format :

"Stuffs": [
    {
        "Name": "Darts",
        "Type": "Fun Stuff"
    },
    {
        "Name": "Clean Toilet",
        "Type": "Boring Stuff"
    }
]

In PowerShell 3, we can obtain a list of Stuffs :

$JSON = Get-Content $jsonConfigFile | Out-String | ConvertFrom-Json

Assuming we don't know the exact contents of the list, including the ordering of the objects, how can we retrieve the object(s) with a specific value for the Name field ?

Brute force, we could iterate through the list :

foreach( $Stuff in $JSON.Stuffs ) { 

But I am hopeful there exists a more direct mechanism ( similar to Lync or Lambda expressions in C# ).

回答1:

$json = @"
{
"Stuffs": 
    [
        {
            "Name": "Darts",
            "Type": "Fun Stuff"
        },

        {
            "Name": "Clean Toilet",
            "Type": "Boring Stuff"
        }
    ]
}
"@

$x = $json | ConvertFrom-Json

$x.Stuffs[0] # access to Darts
$x.Stuffs[1] # access to Clean Toilet
$darts = $x.Stuffs | where { $_.Name -eq "Darts" } #Darts

回答2:

I just asked the same question here: https://stackoverflow.com/a/23062370/3532136 It has a good solution. I hope it helps ^^. In resume, you can use this:

The Json file in my case was called jsonfile.json:

{
    "CARD_MODEL_TITLE": "OWNER'S MANUAL",
    "CARD_MODEL_SUBTITLE": "Configure your download",
    "CARD_MODEL_SELECT": "Select Model",
    "CARD_LANG_TITLE": "Select Language",
    "CARD_LANG_DEVICE_LANG": "Your device",
    "CARD_YEAR_TITLE": "Select Model Year",
    "CARD_YEAR_LATEST": "(Latest)",
    "STEPS_MODEL": "Model",
    "STEPS_LANGUAGE": "Language",
    "STEPS_YEAR": "Model Year",
    "BUTTON_BACK": "Back",
    "BUTTON_NEXT": "Next",
    "BUTTON_CLOSE": "Close"
}

Code:

$json = (Get-Content "jsonfile.json" -Raw) | ConvertFrom-Json

$json.psobject.properties.name

Output:

CARD_MODEL_TITLE
CARD_MODEL_SUBTITLE
CARD_MODEL_SELECT
CARD_LANG_TITLE
CARD_LANG_DEVICE_LANG
CARD_YEAR_TITLE
CARD_YEAR_LATEST
STEPS_MODEL
STEPS_LANGUAGE
STEPS_YEAR
BUTTON_BACK
BUTTON_NEXT
BUTTON_CLOSE

Thanks to mjolinor.

回答3:

David Brabant's answer led me to what I needed, with this addition:

x.Stuffs | where { $_.Name -eq "Darts" } | Select -ExpandProperty Type

回答4:

This is my json data:

[
   {
      "name":"Test",
      "value":"TestValue"
   },
   {
      "name":"Test",
      "value":"TestValue"
   }
]

Powershell script:

$data = Get-Content "Path to json file" | Out-String | ConvertFrom-Json

foreach ($line in $data) {
     $line.name
}