我有下面的脚本，我一生都无法理解为什么它给了我“你不能在空值表达式上调用方法”。它在两个地方出错。
Which computer?: NFDW2206
What is the AssetID?: 00000007
Checking NFDW2206 to see if the Registry Key exists..
You cannot call a method on a null-valued expression.
At \\NFDNT007\Dept\Corporate\IT\Network Services\Documentation\Asset Tag.ps1:11 char:33
+ $regassetid = $regKey.GetValue <<<< ("AssetID")
+ CategoryInfo : InvalidOperation: (GetValue:String) [], RuntimeException
+ FullyQualifiedErrorId : InvokeMethodOnNull
The Key does not exist. Writing AssetID.....
You cannot call a method on a null-valued expression.
At \\NFDNT007\Dept\Corporate\IT\Network Services\Documentation\Asset Tag.ps1:18 char:20
+ $regKey.Setvalue <<<< ('AssetID', $AssetID, 'String')
+ CategoryInfo : InvalidOperation: (Setvalue:String) [], RuntimeException
+ FullyQualifiedErrorId : InvokeMethodOnNull
代码如下
$Computer = Read-Host "Which computer?"
$AssetID = Read-Host "What is the AssetID?"
if (($Computer -eq "") -or ($AssetID -eq "")) {
Write-Host "Error: A blank parameter was detected" -BackgroundColor Black -ForegroundColor Yellow
} else {
if (Test-Connection -comp $Computer -count 1 -quiet) {
Write-Host "Checking $Computer to see if the Registry Key exists.."
$reg = [Microsoft.Win32.RegistryKey]::OpenRemoteBaseKey("LocalMachine", $Computer)
$regKey = $reg.OpenSubKey("SOFTWARE\Multek Northfield")
$regassetid = $regKey.GetValue("AssetID")
if ($regassetid -eq $null) {
Write-Host "The Key does not exist. Writing AssetID....."
$reg = [Microsoft.Win32.RegistryKey]::OpenRemoteBaseKey("LocalMachine", $Computer)
$regKey = $reg.OpenSubKey("SOFTWARE\Multek Northfield",$True) ## $True = Write
$regKey.Setvalue('AssetID', $AssetID, 'String')
} else {
$OverWrite = Read-Host "AssetID exists do you wish to continue?"
if (($OverWrite -eq "y") -or ($OverWrite -eq "yes")) {
$reg = [Microsoft.Win32.RegistryKey]::OpenRemoteBaseKey('LocalMachine', $Computer)
$regKey = $reg.OpenSubKey("SOFTWARE\Multek Northfield",$True) ## $True = Write
$regKey.Setvalue("AssetID", $AssetID, "String")
}
}
} else {
Write-Host "Error: $computer is offline..." -BackgroundColor Black -ForegroundColor Yellow
}
}