object - 使用 PowerShell 的 Add-Member 会导致错误

Question

为什么下面的脚本会出现以下错误？

"Add-Member : Cannot process command because of one or more missing
mandatory parameters: InputObject.
+ $obj = Add-Member <<<< -MemberType NoteProperty -Name ComputerName -Value $ComputerName
+ CategoryInfo : InvalidArgument: (:) [Add-Member], ParameterBindingException
+ FullyQualifiedErrorId : MissingMandatoryParameter,Microsoft.PowerShell.Commands.AddMemberCommand"

脚本

# Receives the computer name and stores the required results in $obj.
Function WorkerNetworkAdaptMacAddress {
    Param($ComputerName)

    $colItems = GWMI -cl "Win32_NetworkAdapterConfiguration" -name "root\CimV2" -comp $ComputerName -filter "IpEnabled = TRUE"
    $obj = New-Object -TypeName PSobject
    ForEach ($objItem in $colItems)
    {
        $obj = Add-Member -MemberType NoteProperty -Name ComputerName -Value $ComputerName
        $obj = Add-Member -MemberType NoteProperty -Name MacAddress -Value $objItem.MacAddress
        $obj = Add-Member -MemberType NoteProperty -Name IPAdress -Value $objitem.IpAddress
    }
    Write-Output $obj
}

# Receives the computer name and passes it to WorkerNetworkAdaptMacAddress.

Function Get-NetworkAdaptMacAddress {
    begin {}
    process{
        WorkerNetworkAdaptMacAddress -computername $_
    }
    end {}
}

# Passes a computer name to get-networkAdaptMacAddress
'tbh00363' | Get-NetworkAdaptMacAddress

Answer 1

您需要移动 PSObject创建进入循环。否则，您将收到属性已存在于对象上的错误。

其次，你需要告诉Add-Member对哪个对象进行操作。您可以通过将对象通过管道传输到 cmdlet 或在 InputObject 参数上指定来完成此操作。最后，通过在最后一次 Add-Member 调用上指定 PassThru 开关，将对象返回到管道:

ForEach ($objItem in $colItems)
{
    $obj = New-Object -TypeName PSobject
    Add-Member -InputObject $obj -MemberType NoteProperty -Name ComputerName -Value $ComputerName
    Add-Member -InputObject $obj -MemberType NoteProperty -Name MacAddress -Value $objItem.MacAddress
    Add-Member -InputObject $obj -MemberType NoteProperty -Name IPAddress -Value $objitem.IpAddress -PassThru
}

或者，您可以使用 New-Object's 来简化该过程。 -Property 参数:

Get-WmiObject Win32_NetworkAdapterConfiguration -ComputerName $ComputerName -Filter "IpEnabled=TRUE" | Foreach-Object {
    New-Object -TypeName PSobject -Property @{
        ComputerName=$ComputerName
        MacAddress=$_.MacAddress
        IPAddress=$_.IpAddress
    }
}

或者使用Select-Object :

Get-WmiObject ... | Select-Object @{n='ComputerName';e={$_.__SERVER}},MacAddress,IpAddress