如何使用点符号字符串从 PSObject 获取子对象

Question

假设我有以下 JSON

{
    "firstName":  "Frank",
    "lastName":  "Smith",
    "age":  "25",
    "address":  {
                    "streetAddress":  "21 3rd st",
                    "city":  "New York",
                    "state":  "NY",
                    "postalCode":  "10021"
                },
    "phoneNumber":  [
                        {
                            "type":  "home",
                            "number":  "212 555-1234"
                        },
                        {
                            "type":  "fax",
                            "number":  "646 555-4567"
                        }
                    ]
}

我需要能够使用点分符号更新值。

$path = "C:\somePath\test.json"
$node = "address.streetAddress"         # should also work with "phoneNumber[0].number"
$value = "21 Jump St."

$config = Get-Content -Path $path -Raw | ConvertFrom-Json
$config.$node = $value
Write-Host $config.$node

#Set-Content $path $($config | ConvertTo-Json)

我遇到的问题是找不到属性。

Exception setting "address.streetAddress": "The property 'address.streetAddress' cannot be found on this object. Verify that the property exists and can be set."

我需要做什么才能传递点分符号并更新适当的值？

Answer 1

虽然您可以将单个属性名称放入变量中并使用它来访问属性，但您不能对多个点属性执行此操作。您可以使用 Invoke-Expression:

解决此问题

Invoke-Expression "`$config.$node = `$value"

Answer 2

最短路线是：

$config.$($node) = $value

嵌套层级无关紧要，您可以这样做：

$config.$($node).$($subnode).$($subSubNode) = $value

您还可以像这样引用对象中的属性：

$config.$($node.nodename)=$value

如何使用点符号字符串从 PSObject 获取子对象

How to get child object from PSObject using dot notation string

syntax

powershell