I'm trying to extract certain values from a sorted hash table using Select-String.
This works, but why are there extra blank lines in the output?
cls
$fruits = #{"1" = "apple"; "2" = "lemon"; "3" = "orange"; "4" = "apricot"}
foreach ($fruit in $fruits.GetEnumerator() | Sort-Object Value) {
$fruit.Value | Select-String -pattern "ap" -SimpleMatch
}
I think you're getting the empty values because for each item you're doing a Select-String, which is returning a value sometimes but nothing at other times - those nothings are the blank lines.
Try something like this that uses Where-Object:
$fruits.Values | Sort-Object | Where-Object { $_ -match "ap" }
I'm using PowerShell 3.0.
I did two lines of code
PS C:\> $fruits = #{"1" = "apple"; "2" = "lemon"; "3" = "orange"; "4" = "apricot"}
PS C:\> $fruits.Values -like 'ap*'
apricot
apple
PS C:\>
Further Investigating
Seems to be that when there is no match it returns NULL.
foreach($key in $fruits.Keys){(Select-String -Pattern 'ap' -SimpleMatch -InputObject $fruits[$key]) -eq $NULL}
Since it is not redirecting to a variable it just prints NULL to the Host. That's my assumption (assume).
Strange...good question.
Related
This question is more about my understanding Powershell's objects rather than solving this practical example. I know there are other ways of separating out a page number from a string.
In my example I want to do this by accessing the object-match-value of the piped pattern match.
# data
$headerString = 'BARTLETT-BEDGGOOD__PAGE_5 BEECH-BEST__PAGE_6'
# require the number of page only
$regexPageNum = '([0-9]$)'
# split the header string into two separate strings to access page numbers
[string[]]$pages = $null
$pages = $headerString -split ' '
# access page numbers using regex pattern
$pages[0] | Select-String -AllMatches -Pattern $regexPageNum | Select-Object {$_.Matches.Value}
The output is:
$_.Matches.Value
----------------
5
Okay. So far so good. I see the page number of array member pages[0] But how do I take this value from the object? The following does not work.
$x = $pages[0] | Select-String -AllMatches -Pattern $regexPageNum | Select-Object {$_.Matches.Value}
Write-Host "Here it is:"$x
Output:
Here it is: #{$_.Matches.Value=5}
Instead of assigning the value 5 to the variable $x Powershell assigns, what looks to me: a hash table with an object description as its only member?
But if I try to access my variable using "Brackets for Access" Reference: hashtables Powershell indicates that variable $x is in fact an array.
x = $pages[0] | Select-String -AllMatches -Pattern $regexPageNum | Select-Object {$_.Matches.Value}
Write-Host "Here it is:"$x
$y = $x[$_.Matches.Value]
Write-Host "What about now:"$y
Output:
Here it is: #{$_.Matches.Value=5}
InvalidOperation:
Line |
33 | $y = $x[$_.Matches.Value]
| ~~~~~~~~~~~~~~~~~~~~~~~~~
| Index operation failed; the array index evaluated to null.
What about now:
Okay. At this stage I know I'm being silly. But the point I'm trying to make is: How can I retrieve the value I want when I'm done with the Powershell object?
You can use $x.{ $_.Matches.Value } to access the value.
$x = $pages[0] | Select-String -AllMatches -Pattern $regexPageNum | Select-Object { $_.Matches.Value }
$x.{ $_.Matches.Value } # This will print 5
ie, You would have to wrap the property name inside {} since the property name contains "."
Instead of this way, I would suggest you to create a calculated property using Select-Object which makes the code more readable.
$x = $pages[0] | Select-String -AllMatches -Pattern $regexPageNum | Select-Object #{Name = 'PageNumber'; Expression = {$_.Matches.Value}}
$x.PageNumber
#Access matches in case of single match
$x = "red blue yellow green" | select-string -Pattern 'blue'
$x.matches.value
#Output
blue
#Access matches in case of multi match
$x = "red blue yellow green blue" | select-string -Pattern 'blue' -AllMatches
$x.matches.value
#Output
blue
blue
When you use a scriptblock as a parameter to Select-Object the return value will contain a property whose name matches the source code of the script block...
PS> #{ "aaa" = "bbb" } | select-object { $_.aaa; <# xxx #> }
$_.aaa; <# xxx #>
-------------------
bbb
In this pathological case, if I want to access the property I can't use the name in the default "dotted" notation because it contains reserved characters, but you can access it if you quote the property name:
PS> $x = #{ "aaa" = "bbb" } | select-object { $_.aaa; <# xxx #> }
# note the leading and trailing spaces in the string because the
# the original scriptblock source contains spaces between the "{" and "}"
PS> $x.' $_.aaa; <# xxx #> '
bbb
In your case you'd do this:
PS> $x = $pages[0] | Select-String -AllMatches -Pattern $regexPageNum | Select-Object {$_.Matches.Value}
PS> $x.'$_.Matches.Value'
Other options work too:
$x = $pages[0] `
| Select-String -AllMatches -Pattern $regexPageNum `
| Select-Object {$_.Matches.Value}
# get the property whose name is contained in the $name variable
PS> $name = '$_.Matches.Value'
PS> $x.$name
5
# the scriptblock gets converted into a string, and then that string
# is used as a property name
PS> $x.{$_.Matches.Value}
5
# note the whitespace in both scriptblocks has to match *exactly* otherwise the property name won't be found
PS> $x.{ $_.Matches.Value }
ParentContainsErrorRecordException: The property ' $_.Matches.Value ' cannot be found on this object. Verify that the property exists.
but...
There's an easier way - if you pass a hashtable to Select-Object instead of a scriptblock you can specify the name of the property - e.g.
PS> $x = $pages[0] `
| Select-String -AllMatches -Pattern $regexPageNum `
| Select-Object #{ "l"="Count"; "e"={$_.Matches.Value} }
PS> $x
Count
-----
5
PS> $x.Count
5
References:
about_Calculated_Properties - Hashtable key definitions
I'm trying to write a script that counts all comments in multiple files, including both single line (//) and multi-line (/* */) comments and prints out the total. So, the following file would return 4
// Foo
var text = "hello world";
/*
Bar
*/
alert(text);
There's a requirement to include specific file types and exclude certain file types and folders, which I already have working in my code.
My current code is:
( gci -include *.cs,*.aspx,*.js,*.css,*.master,*.html -exclude *.designer.cs,jquery* -recurse `
| ? { $_.FullName -inotmatch '\\obj' } `
| ? { $_.FullName -inotmatch '\\packages' } `
| ? { $_.FullName -inotmatch '\\release' } `
| ? { $_.FullName -inotmatch '\\debug' } `
| ? { $_.FullName -inotmatch '\\plugin-.*' } `
| select-string "^\s*//" `
).Count
How do I change this to get multi-line comments as well?
UPDATE: My final solution (slightly more robust than what I was asking for) is as follows:
$CodeFiles = Get-ChildItem -include *.cs,*.aspx,*.js,*.css,*.master,*.html -exclude *.designer.cs,jquery* -recurse |
Where-Object { $_.FullName -notmatch '\\(obj|packages|release|debug|plugin-.*)\\' }
$TotalFiles = $CodeFiles.Count
$IndividualResults = #()
$CommentLines = ($CodeFiles | ForEach-Object{
#Get the comments via regex
$Comments = ([regex]::matches(
[IO.File]::ReadAllText($_.FullName),
'(?sm)^[ \t]*(//[^\n]*|/[*].*?[*]/)'
).Value -split '\r?\n') | Where-Object { $_.length -gt 0 }
#Get the total lines
$Total = ($_ | select-string .).Count
#Add to the results table
$IndividualResults += #{
File = $_.FullName | Resolve-Path -Relative;
Comments = $Comments.Count;
Code = ($Total - $Comments.Count)
Total = $Total
}
Write-Output $Comments
}).Count
$TotalLines = ($CodeFiles | select-string .).Count
$TotalResults = New-Object PSObject -Property #{
Files = $TotalFiles
Code = $TotalLines - $CommentLines
Comments = $CommentLines
Total = $TotalLines
}
Write-Output (Get-Location)
Write-Output $IndividualResults | % { new-object PSObject -Property $_} | Format-Table File,Code,Comments,Total
Write-Output $TotalResults | Format-Table Files,Code,Comments,Total
To be clear: Using string matching / regular expressions is not a fully robust way to detect comments in JavaScript / C# code, because there can be false positives (e.g., var s = "/* hi */";); for robust parsing you'd need a language parser.
If that is not a concern, and it is sufficient to detect comments (that start) on their own line, optionally preceded by whitespace, here's a concise solution (PSv3+):
(Get-ChildItem -include *.cs,*.aspx,*.js,*.css,*.master,*.html -exclude *.designer.cs,jquery* -recurse |
Where-Object { $_.FullName -notmatch '\\(obj|packages|release|debug|plugin-.*)' } |
ForEach-Object {
[regex]::matches(
[IO.File]::ReadAllText($_.FullName),
'(?sm)^[ \t]*(//[^\n]*|/[*].*?[*]/)'
).Value -split '\r?\n'
}
).Count
With the sample input, the ForEach-Object command yields 4.
Remove the ^[ \t]* part to match comments starting anywhere on a line.
The solution reads each input file as a single string with [IO.File]::ReadAllText() and then uses the [regex]::Matches() method to extract all (potentially line-spanning) comments.
Note: You could use Get-Content -Raw instead to read the file as a single string, but that is much slower, especially when processing multiple files.
The regex uses in-line options s and m ((?sm)) to respectively make . match newlines too and to make anchors ^ and $ match line-individually.
^[ \t]* matches any mix of spaces and tabs, if any, at the start of a line.
//[^\n]*$ matches a string that starts with // through the end of the line.
/[*].*?[*]/ matches a block comment across multiple lines; note the lazy quantifier, *?, which ensures that very next instance of the closing */ delimiter is matched.
The matched comments (.Value) are then split into individual lines (-split '\r?\n'), which are output.
The resulting lines across all files are then counted (.Count)
As for what you tried:
The fundamental problem with your approach is that Select-String with file-info object input (such as provided by Get-ChildItem) invariably processes the input files line by line.
While this could be remedied by calling Select-String inside a ForEach-Object script block in which you pass each file's content as a single string to Select-String, direct use of the underlying regex .NET types, as shown above, is more efficient.
An IMO better approach is to count net code lines by removing single/multi line comments.
For a start a script that handles single files and returns for your above sample.cs the result 5
((Get-Content sample.cs -raw) -replace "(?sm)^\s*\/\/.*?$" `
-replace "(?sm)\/\*.*?\*\/.*`n" | Measure-Object -Line).Lines
EDIT: without removing empty lines, build the difference from total lines
## Q:\Test\2018\10\31\SO_53092258.ps1
$Data = Get-ChildItem *.cs | ForEach-Object {
$Content = Get-Content $_.FullName -Raw
$TotalLines = (Measure-Object -Input $Content -Line).Lines
$CodeLines = ($Content -replace "(?sm)^\s*\/\/.*?$" `
-replace "(?sm)\/\*.*?\*\/.*`n" | Measure-Object -Line).Lines
$Comments = $TotalLines - $CodeLines
[PSCustomObject]#{
File = $_.FullName
Lines = $TotalLines
Comments= $Comments
}
}
$Data
"="*40
"TotalLines={0} TotalCommentLines={1}" -f (
$Data | Measure-Object -Property Lines,Comments -Sum).Sum
Sample output:
> Q:\Test\2018\10\31\SO_53092258.ps1
File Lines Comments
---- ----- --------
Q:\Test\2018\10\31\example.cs 10 5
Q:\Test\2018\10\31\sample.cs 9 4
============================================
TotalLines=19 TotalCommentLines=9
I'm working on a script that combines parts of two text files. These files are not too large (about 2000 lines each).
I'm seeing strange output from select-string that I don't think should be there.
Here's samples of my two files:
CC.csv - 2026 lines
LS126L47L6/1L2#519,07448,1,B
LS126L47L6/1R1-1#503,07449,1,B
LS126L47L6/1L3#536,07450,1,B
LS126L47L6/2R1#515,07451,1,B
LS126L47L6/10#525,07452,1,B
LS126L47L6/1L4#538,07453,1,B
GI.txt - 1995 lines
07445,B,SH,1
07446,B,SH,1
07448,B,SH,1
07449,B,SH,1
07450,B,SH,1
07451,B,SH,1
07452,B,SH,1
07453,B,SH,1
07454,B,SH,1
And here's a sample of the output file:
output in myfile.csv
LS126L47L6/3R1#516,07446,1,B
LS126L47L6/1L2#519,07448,1,B
LS126L47L6/1R1-1#503,07449,1,B
System.Object[],B
LS126L47L6/2R1#515,07451,1,B
This is the script I'm using:
sc ./myfile.csv "col1,col2,col3,col4"
$mn = gc cc.csv | select -skip 1 | % {$_.tostring().split(",")[1]}
$mn | % {
$a = (gc cc.csv | sls $_ ).tostring() -replace ",[a-z]$", ""
if (gc GI.txt | sls $_ | select -first 1)
{$b = (gc GI.txt | sls $_ | select -first 1).tostring().split(",")[1]}
else {$b = "NULL"
write-host "$_ is not present in GI file"}
$c = $a + ',' + $b
ac ./myfile.csv -value $c
}
The $a variable is where I am sometimes seeing the returned string as System.Object[]
Any ideas why? Also, this script takes quite some time to finish. Any tips for a newb on how to speed it up?
Edit: I should add that I've taken one line from the cc.csv file, saved in a new text file, and run through the script in console up through assigning $a. I can't get it to return "system.object[]".
Edit 2: After follow the advice below and trying a couple of things I've noticed that if I run
$mn | %{(gc cc.csv | sls $_).tostring()}
I get System.Object[].
But if I run
$mn | %{(gc cc.csv | sls $_)} | %{$_.tostring()}
It comes out fine. Go figure.
The problem is caused by a change in multiplicity of matches. If there are multiple matching elements an Object[] array (of MatchInfo elements) is returned; a single matching element results in a single MatchInfo object (not in an array); and when there are no matches, null is returned.
Consider these results, when executed against the "cc.csv" test-data supplied:
# matches many
(gc cc.csv | Select-String "LS" ).GetType().Name # => Object[]
# matches one
(gc cc.csv | Select-String "538").GetType().Name # => MatchInfo
# matches none
(gc cc.csv | Select-String "FAIL") # => null
The result of calling ToString on Object[] is "System.Object[]" while the result is a more useful concatenation of the matched values when invoked directly upon a MatchInfo object.
The immediate problem can be fixed with selected | Select -First 1, which will result in a MatchInfo being returned for the first two cases. Select-String will still search the entire input - extra results are simply discarded.
However, it seems like the look-back into "cc.csv" (with the Select-String) could be eliminated entirely as that is where $_ originally comes from. Here is a minor [untested] adaptation, of what it may look like:
gc cc.csv | Select -Skip 1 | %{
$num = $_.Split(",")[1]
$a = $_ -Replace ",[a-z]$", ""
# This is still O(m*n) and could be improved with a hash/set probe.
$gc_match = Select-String $num -Path gi.csv -SimpleMatch | Select -First 1
if ($gc_match) {
# Use of "Select -First 1" avoids the initial problem; but
# it /may/ be more appropriate for an error to indicate data problems.
# (Likewise, an error in the original may need further investigation.)
$b = $gc_match.ToString().Split(",")[1]
} else {
$b = "NULL"
Write-Host "$_ is not present in GI file"
}
$c = $a + ',' + $b
ac ./myfile.csv -Value $c
}
If I've got a variable $count with a number in it, is there a one-liner to set a variable to either true or false depending on whether $count = 1?
I thought that
$result = ($count -eq 1)
would do it, but I end up with a value of "1" or null stored in it (depending on whether it's 1 or not).
Any idea what I'm doing wrong?
EDIT: My Mistake - I didn't actually have "1" in that variable. I had an ArrayList that looked like it was the number 1. Closing this.
Full code:
get-acl C:\Windows\System32\drivers\etc | select -expand access | where {$_.IdentityReference -eq "SomeACL"} | measure | select -expand count -OutVariable aclCount
$aclFound = ($aclCount –eq 1)
$TodayDate = Get-Date -Format "dd/MM/yyyy hh:mm:ss"
Add-Content f:\myfile.log "$TodayDate $aclFound "
Fixed it by putting a [0] after the $aclCount on line 2.
(Obviously the ACL in there was the one I was checking for)
You can always use an If/Then/Else to do it.
If($Count -eq 1){$result = $true}else{$result = $false}
Can't reproduce.
PS C:\> $count = 3
PS C:\> $result = ($count -eq 1)
PS C:\> $result
False
PS C:\> $result.GetType().Name
Boolean
Main Script
$Computers = Get-Content .\computers.txt
If ( test-path .\log.txt ) {
$Log_Successful = Import-CSV .\log.txt | Where-Object {$_.Result -eq "Succesful"}
} ELSE {
Add-Content "Computer Name,Is On,Attempts,Result,Time,Date"
}
$Log_Successful | format-table -autosize
Issues:
Log_Successful."Computer Name" works fine, but if i change 4 to read as the following
$Log_Successful = Import-CSV .\log.txt | Where-Object {$_.Result -eq "Failed"}
Log_Successful."Computer Name" no longer works... Any ideas why?
Dataset
Computer Name,Is On,Attempts,Result,Time,Date
52qkkgw-94210jv,False,1,Failed,9:48 AM,10/28/2012
HELLBOMBS-PC,False,1,Successful,9:48 AM,10/28/2012
52qkkgw-94210dv,False,1,Failed,9:48 AM,10/28/2012
In case of "Successful" a single object is returned. It contains the property "Computer Name". In case of "Failed" an array of two objects is returned. It (the array itself) does not contain the property "Computer Name". In PowerShell v3 in some cases it is possible to use notation $array.SomePropertyOfContainedObject but in PowerShell v2 it is an error always. That is what you probably see.
You should iterate through the array of result objects, e.g. foreach($log in $Log_Successful) {...} and access properties of the $log objects.
And the last tip. In order to ensure that the result of Import-Csv call is always an array (not null or a single object) use the #() operator.
The code after fixes would be:
$logs = #(Import-Csv ... | where ...)
# $logs is an array, e.g. you can use $logs.Count
# process logs
foreach($log in $logs) {
# use $log."Computer Name"
}
I'm not sure if this is the problem but you have a typo, in Where-Object you compare against "Succesful" and the value in the file is "Successful" (missing 's').
Anyway, what's not working?