PowerShell中Get-WmiObject针对PSCustomObject的错误处理问题

问题背景 #

脚本核心需求：

• 将最终输出保存至TXT文件，无法获取的信息留空
• 从CSV文件读取PC名称与用户ID，适配用户无对应PC或工作站未开机的场景
• 目前Get-ADUser相关逻辑正常，但Get-WmiObject的try-catch未生效，异常时无法将对应信息留空

用户提供的原始脚本 #

$userName1 = "UserX"
$Computernames = Import-CSV 'C:\PCnames.csv' -Delimiter ';'
$pcName = $Computernames.Where({ $_."User ID" -match $userName1})."PC Name"

$aProperties = @(
        'Name'
        'mail'
        'OfficePhone'
        'Description'
        'PasswordLastSet'
        'LastBadPasswordAttempt'
        'LockedOut'
        'Enabled'
        'msDS-UserPasswordExpiryTimeComputed'
    )
$aUser = Get-Aduser -Identity $userName1 -Properties $aProperties
$aUser

$IP = try {Get-WmiObject Win32_NetworkAdapterConfiguration -Computername $pcName -ea stop |
        Where { $_.IPAddress } |
        Select -Expand IPAddress | 
        Where { $_ -like '10.33*' -or $_ -like '10.44*'} } 
catch {""}

$Model = try { (Get-WmiObject -Class Win32_ComputerSystem -ComputerName $pcName -ea stop ).Model}
catch {""}

$OS =try { Get-WmiObject win32_operatingsystem -Computername $pcName -ea stop | select csname, @{LABEL='LastBootUpTime';EXPRESSION={$_.ConverttoDateTime($_.lastbootuptime)}}}
catch{""}

[pscustomobject]@{   
    UserID                      = $aUser.Name
    Mail                        = $aUser.mail
    Phone                       = $aUser.OfficePhone
    Hostname                    = $pcName
    LockedStatus                = $aUser.LockedOut
    AccountEnabled              = $aUser.Enabled
    LastBadPasswordAttempt      = $aUser.LastBadPasswordAttempt
    OSVersion                   = $OSVersion.Version
    OSName                      = $OSVersion.Name
    IPAddress                   = $IP
    Model                       = $Model 
} 

问题分析与修复方案 #

1. 先处理$pcName为空的场景 #

当CSV中没有对应用户的PC记录时，$pcName会为空，此时WMI调用会抛出非终止错误（即使加了-ea stop），需要提前判断并初始化变量：

# 初始化所有WMI相关变量为空
$IP = ""
$Model = ""
$OSInfo = [pscustomobject]@{Version=""; Name=""; LastBootUpTime=""}

if (-not [string]::IsNullOrEmpty($pcName)) {
    # 仅当PC名称存在时才执行远程查询
    # ...后续WMI/CIM逻辑...
}

2. 修复try-catch生效问题 #

Get-WmiObject的部分错误属于非终止错误，需确保-ErrorAction Stop正确传递；同时修正原始脚本中OSVersion未定义的变量引用错误，需调整WMI查询逻辑获取完整OS信息。

3. 替换为Get-CimInstance（推荐） #

Get-WmiObject已被弃用，Get-CimInstance的异常处理更一致，且支持现代PowerShell特性，能更稳定捕获远程连接失败等异常。

4. 输出到TXT文件 #

将最终构建的自定义对象导出到TXT，可使用Out-File保证格式可读性：

$result | Out-File -Path "C:\UserInfo.txt" -Encoding UTF8

修改后的完整脚本 #

$userName1 = "UserX"
$Computernames = Import-CSV 'C:\PCnames.csv' -Delimiter ';'
$pcName = $Computernames.Where({ $_."User ID" -match $userName1})."PC Name"

# 获取AD用户信息
$aProperties = @(
    'Name','mail','OfficePhone','Description','PasswordLastSet',
    'LastBadPasswordAttempt','LockedOut','Enabled','msDS-UserPasswordExpiryTimeComputed'
)
$aUser = Get-Aduser -Identity $userName1 -Properties $aProperties

# 初始化WMI相关变量为空
$IP = ""
$Model = ""
$OSInfo = [pscustomobject]@{
    Version = ""
    Name = ""
    LastBootUpTime = ""
}

# 仅当PC名称有效时执行远程查询
if (-not [string]::IsNullOrEmpty($pcName)) {
    # 获取IP地址
    $IP = try {
        Get-CimInstance Win32_NetworkAdapterConfiguration -ComputerName $pcName -ErrorAction Stop |
        Where-Object { $_.IPAddress } |
        Select-Object -ExpandProperty IPAddress |
        Where-Object { $_ -like '10.33*' -or $_ -like '10.44*' }
    } catch { "" }

    # 获取设备型号
    $Model = try {
        (Get-CimInstance Win32_ComputerSystem -ComputerName $pcName -ErrorAction Stop).Model
    } catch { "" }

    # 获取OS信息
    $OSInfo = try {
        $os = Get-CimInstance Win32_OperatingSystem -ComputerName $pcName -ErrorAction Stop
        [pscustomobject]@{
            Version = $os.Version
            Name = $os.Name.Split("|")[0].Trim()
            LastBootUpTime = $os.LastBootUpTime
        }
    } catch {
        [pscustomobject]@{Version=""; Name=""; LastBootUpTime=""}
    }
}

# 构建结果对象
$result = [pscustomobject]@{   
    UserID                      = $aUser.Name
    Mail                        = $aUser.mail
    Phone                       = $aUser.OfficePhone
    Hostname                    = $pcName ?? ""
    LockedStatus                = $aUser.LockedOut
    AccountEnabled              = $aUser.Enabled
    LastBadPasswordAttempt      = $aUser.LastBadPasswordAttempt
    OSVersion                   = $OSInfo.Version
    OSName                      = $OSInfo.Name
    LastBootUpTime              = $OSInfo.LastBootUpTime
    IPAddress                   = $IP -join ", "  # 多个IP用逗号分隔
    Model                       = $Model 
} 

# 输出到TXT文件
$result | Out-File -Path "C:\UserInfo.txt" -Encoding UTF8
# 可选：输出为CSV便于后续处理
# $result | Export-Csv -Path "C:\UserInfo.csv" -Delimiter ";" -NoTypeInformation -Encoding UTF8

内容的提问来源于stack exchange，提问作者Toon