从Powershell输出Search-String中提取单词

Question

Hi All I'm trying to extract a word from a text output. It should be pretty easy but I've already spent so much time on it. Right now I can extract the line but not just the word.

For example

w32tm /query /status | Select-String -pattern "CMOS"

outputs the line "Source: Local CMOS Clock"

I only want to extract "Local CMOS Clock"

$var1=w32tm /query /status | Select-String -pattern "CMOS"

$var2=($var1 -split ':')[1] | Out-String

I was able to come up with the above it seems to work I'm not sure if there's a better way, I'm trying to evaluate it through a true/false seem to always pass as true though For example

if($var2 = "Local CMOS Clock"){
Write-Output "True";
}Else{
Write-Output "False";
}

Always true: even when the condition is wrong

thanks in advance.

Answer 1

I'm not entirely sure of your motives, but here's a cleaner way to get to the answer you're looking for:

Build a PSObject containing the output

The PSObject will contain the output of w32tm. The code works by piping the command output through a loop, at the beginning we make a HashTable and then this is used to build a PowerShell object which is easier to manipulate:

# Pipe the w32tm command through a foreach
# Build a hashtable object containing the keys
# $_ represents each entry in the command output, which is then split by ':'
$w32_obj = w32tm /query /status | ForEach-Object -Begin {$w32_dict = @{}} -Process {
    # Ignore blank entries
    if ($_ -ne '') {
        $fields = $_ -split ': '
        # This part sets the elements of the w32_dict. 
        # Some rows contain more than one colon, 
        # so we combine all (except 0) the split output strings together using 'join'
        $w32_dict[$fields[0]] = $($fields[1..$($fields.Count)] -join ':').Trim()
    }
} -End {New-Object psobject -Property $w32_dict}

View the PSObject

Simply run this to display the new PSObject that has been created:

$w32_obj

Now check the 'Source'

Now we can ask for the 'Source' object from $w32_obj by using the dot-notation: $w32_obj.Source :

if($w32_obj.Source -eq "Local CMOS Clock"){
Write-Output "True";
}Else{
Write-Output "False";
}

Further reading

This shows the conversion from HashTable to PSobject and vice-versa

PSCustomObject to Hashtable

Answer 2

here's yet another way to get the False/True from w32tm. my system does not have "cmos" in the output, so i use 'system clock', but the idea will work for your situation.

[bool]((w32tm /query /status) -match 'system clock')

the above returns a $True on my system. that seems a tad more direct than the method you used. [ grin ]

take care,
lee