I'm using a foreach loop against an array populated by a CSV. The CSV contains lines of product names, current support status, and a version number for when support was started. Sometimes these support versions are comma separated for a variety of reasons.
When a comma-separated version is found in a row, that row is removed from the array. A new row is then created and added to the array for each version found.
The issue I'm having is that if I have a version of "7,8,9" I end up with three rows all listing version 9. Troubleshooting the script shows that the values are being split and picked up correctly, but the array seems to be updating every value with whatever the latest is. For example, the first pass would make version 7, second pass has two instances of v8, last pass ends up with v9 3 times.
How do I make the += operator not update existing rows?
foreach ($line in $sheet)
{
if ($line.'Support Started' -cmatch ",")
{
$sheet = $sheet -ne $line
$line.'Support Started'.Split(",") |
ForEach
{
$subver = $_
$line.'Support Started' = $subver
$sheet = $sheet += ($line)
}
}
}
To provide more info, if I use the following:
write-host $line
$sheet += $line
write-host $line
on a file with 7,8,9 as the version, I get the following output:
Product1,Supported,7
Product1,Supported,7
Product1,Supported,8
Product1,Supported,8
Product1,Supported,9
Product1,Supported,9
When checking the value of $sheet, I get:
Product1,Supported,9
Product1,Supported,9
Product1,Supported,9
Are you sure that you are not reading the file using Import-Csv?
The reason you are having problem is that when you do
foreach ($line in $sheet)
...
then the variable $line is not a copy of the line in $sheet, but a reference to the line in the sheet variable. I.e. when you change $line you are in fact changing $sheet in place.
I would try not to change $sheet while operating on the data, but instead create a new array that can hold all the data. Something like this:
$sheet = Import-Csv data.csv
$newsheet = #()
foreach ($line in $sheet)
{
if ($line.'Support Started' -cmatch ",")
{
$a = $line.'Support Started'.Split(",")
ForEach ($subver in $a)
{
$line2 = $line.PSObject.Copy()
$line2.'Support Started' = $subver
$newsheet += $line2
}
} else {
$newsheet += $line
}
}
$sheet = $sheet += ($line)
$sheet += $line is already appending $line to $sheet. The extra assignment operation is probably causing your issue.
Not tested:
$sheet =
foreach ($line in $sheet)
{
if ($line.'Support Started' -cmatch ",")
{
$line.'Support Started'.Split(",") |
ForEach
{
$subver = $_
$line.'Support Started' = $subver
$line
}
}
else {$line}
}
Your line
$sheet = $sheet += ($line)
should read (edited)
$sheet += #{'product'=$line.product; 'status'=$line.status; 'support started'=$_}
PS gets slightly confused when $line is from $sheet, remedied by making a new object
Related
I have a function that replaces PackageID in a SCCM task sequence, I would like to capture all those package IDs into a variable, so I would be able to create a report based on that.
The problem is that I already have a foreach loop doing the work, and I can't figure out how to not overwrite the values.
$Driver.PackageID comes from a foreach loop based on $Drivers, which contains
If I run the code I get this as I have Write-Output defined:
Updated code:
function Set-Drivers{
foreach ($Driver in $Drivers) {
Write-Output "Driver Name: $($Driver.Name)"
Write-Output "DriverPackageID: $($Driver.PackageID)"
}
}
$array = #()
$array = Set-Drivers
$hash = [ordered]#{
'DriverName' = $Driver.Name
'DriverID' = $Driver.PackageID
}
$array += New-Object -Typename PSObject -Property $hash
Can someone explain, why I only get the first result in my $array? I can see the values are being overwritten if I run it in debug mode.
Your code is not iterating over the results, but instead only using one of them. This what you intended.
$array = $drivers | foreach {
[ordered]#{
DriverName = $_.Name
DriverID = $_.PackageID
}
}
Your function doesn't return anything. It only writes lines to the console. Then after the function is finished, you create a single object and add that to your array.
Try something like
function Set-Drivers{
$result = foreach ($Driver in $Drivers) {
[PsCustomObject]#{
'DriverName' = $Driver.Name
'DriverID' = $Driver.PackageID
}
}
# output the result
# the comma wraps the result in a single element array, even if it has only one element.
# PowerShell 'flattens' that upon return from the function, leaving the actual resulting array.
,$result
}
$array = Set-Drivers
# show what you've got
$array
I am processing a CSV file, and in one of the columns are cells that have the a string in an array format. Here is what accessing those cells looks like:
$csv = Import-Csv $filelocation
foreach ($line in $csv)
{
Write-Host $line.ColumnName
}
Output:
[Property=[value1,value2,value3]]
[Property=[value1,value2]]
...
You can see that each cell outputs a string with an array structure. I want to treat each individual string as an array with Property[0] = value1, etc.
Is there a simple way to do this? Otherwise, I assume I will need to use Reg Ex.
Oh! Sorry...dont see the file content: ,,,,,"[AsymmetricKey=[]]","[AppAddress=[[AddressType=Reply,Address=urn:ietf:wg:oauth:2.0:oob]]]","[AppAuxiliaryId=[]]",,,,
Ok...if all file content like this we can do somethisng like:
$patch = get-content 'D:\test\testing!.csv'
$pl = $patch.Length - 1
for ($i=0 ; $i -le $pl ; $i++) {
$patch[$i].Replace(",,,,,","").Replace(",,,,","").Replace("Reply,Address","Reply.Address").Split(",")[0]
$patch[$i].Replace(",,,,,","").Replace(",,,,","").Replace("Reply,Address","Reply.Address").Split(",")[1]
$patch[$i].Replace(",,,,,","").Replace(",,,,","").Replace("Reply,Address","Reply.Address").Split(",")[2]
$patch[$i].Replace(",,,,,","").Replace(",,,,","").Replace("Reply,Address","Reply.Address").Split(",")[3]
}
If you want to search some info, think its can be work (but not sure):
$patch = get-content 'D:\test\testing!.csv'
$pl = $patch.Length - 1
for ($i=0 ; $i -le $pl ; $i++) {
$regex = "urn:ietf:wg:oauth:2.0:o2b"
$val = $patch[$i].Replace(",,,,,","").Replace(",,,,","").Replace("Reply,Address","Reply.Address").Split(",")[1]
if ($val.Contains($regex))
{
$val
}
}
You try to do something like this:
$csv = Import-Csv Path:\testing!.csv -Header V1
foreach ($line in $csv) {
$obj = New-Object -TypeName PSObject -Property #{
First = $line
} #| select First #
#{Name='First';Expression={($_.First).Split(";")[1]}}
$obj1 = $obj | select -ExpandProperty First
$obj1.V1
}
I am trying to use $a variable in this script for working with intermediate steps so that I don't have to use $array[$array.Count-1] repeatedly. Similarly for $prop as well . However, values are being overwritten by last value in loop.
$guests = Import-Csv -Path C:\Users\shant_000\Desktop\UploadGuest_test.csv
$output = gc '.\Sample Json.json' | ConvertFrom-Json
$array = New-Object System.Collections.ArrayList;
foreach ($g in $guests) {
$array.Add($output);
$a = $array[$array.Count-1];
$a.Username = $g.'EmailAddress';
$a.DisplayName = $g.'FirstName' + ' ' + $g.'LastName';
$a.Password = $g.'LastName' + '123';
$a.Email = $g.'EmailAddress';
foreach ($i in $a.ProfileProperties.Count) {
$j = $i - 1;
$prop = $a.ProfileProperties[$j];
if ($prop.PropertyName -eq "FirstName") {
$prop.PropertyValue = $g.'FirstName';
} elseif ($prop.PropertyName -eq "LastName") {
$prop.PropertyValue = $g.'LastName';
}
$a.ProfileProperties[$j] = $prop;
}
$array[$array.Count-1] = $a;
}
$array;
All array elements are referencing one actual variable: $output.
Create an entirely new object each time by repeating JSON-parsing:
$jsontext = gc '.\Sample Json.json'
..........
foreach ($g in $guests) {
$a = $jsontext | ConvertFrom-Json
# process $a
# ............
$array.Add($a) >$null
}
In case the JSON file is very big and you change only a few parts of it you can use a faster cloning technique on the changed parts (and their entire parent chain) via .PSObject.Copy():
foreach ($g in $guests) {
$a = $output.PSObject.Copy()
# ............
$a.ProfileProperties = $a.ProfileProperties.PSObject.Copy()
# ............
foreach ($i in $a.ProfileProperties.Count) {
# ............
$prop = $a.ProfileProperties[$j].PSObject.Copy();
# ............
}
$array.Add($a) >$null
}
As others have pointed out, appending $object appends a references to the same single object, so you keep changing the values for all elements in the list. Unfortunately the approach #wOxxOm suggested (which I thought would work at first too) doesn't work if your JSON datastructure has nested objects, because Copy() only clones the topmost object while the nested objects remain references to their original.
Demonstration:
PS C:\> $o = '{"foo":{"bar":42},"baz":23}' | ConvertFrom-Json
PS C:\> $o | Format-Custom *
class PSCustomObject
{
foo =
class PSCustomObject
{
bar = 42
}
baz = 23
}
PS C:\> $o1 = $o
PS C:\> $o2 = $o.PSObject.Copy()
If you change the nested property bar on both $o1 and $o2 it has on both objects the value that was last set to any of them:
PS C:\> $o1.foo.bar = 23
PS C:\> $o2.foo.bar = 24
PS C:\> $o1.foo.bar
24
PS C:\> $o2.foo.bar
24
Only if you change a property of the topmost object you'll get a difference between $o1 and $o2:
PS C:\> $o1.baz = 5
PS C:\> $o.baz
5
PS C:\> $o1.baz
5
PS C:\> $o2.baz
23
While you could do a deep copy it's not as simple and straightforward as one would like to think. Usually it takes less effort (and simpler code) to just create the object multiple times as #PetSerAl suggested in the comments to your question.
I'd also recommend to avoid appending to an array (or arraylist) in a loop. You can simply echo your objects inside the loop and collect the entire output as a list/array by assigning the loop to a variable:
$json = Get-Content '.\Sample Json.json' -Raw
$array = foreach ($g in $guests) {
$a = $json | ConvertFrom-Json # create new object
$a.Username = $g.'EmailAddress'
...
$a # echo object, so it can be collected in $array
}
Use Get-Content -Raw on PowerShell v3 and newer (or Get-Content | Out-String on earlier versions) to avoid issues with multiline JSON data in the JSON file.
I'm populating an array variable $array at some point in my code, for example like below
this
is
an
array
varaible
What if, I wanted to print out the array variable like thisisanarrayvariable as one liner
i took the below approach, but i'am not getting any out while the program is hanging
for ($i=0;$i -le $array.length; $i++)
{ $array[$i] }
obviuosly, i dont want to glue them together like $array[0]+$array[1]+$array[2]..
Hope i can get a better answer.
Joining array elements with no separator
Use the -join operator...
$array -join ''
...or the static String.Join method...
[String]::Join('', $array)
...or the static String.Concat method...
[String]::Concat($array)
For all of the above the result will be a new [String] instance with each element in $array concatenated together.
Fixing the for loop
Your for loop will output each element of $array individually, which will be rendered on separate lines. To fix this you can use Write-Host to write to the console, passing -NoNewline to keep the output of each iteration all on one line...
for ($i = 0; $i -lt $array.Length; $i++)
{
Write-Host -NoNewline $array[$i]
}
Write-Host
The additional invocation of Write-Host moves to a new line after the last array element is output.
If it's not console output but a new [String] instance you want you can concatenate the elements yourself in a loop...
$result = ''
for ($i = 0; $i -lt $array.Length; $i++)
{
$result += $array[$i]
}
The += operator will produce a new intermediate [String] instance for each iteration of the loop where $array[$i] is neither $null nor empty, so a [StringBuilder] is more efficient, especially if $array.Length is large...
$initialCapacity = [Int32] ($array | Measure-Object -Property 'Length' -Sum).Sum
$resultBuilder = New-Object -TypeName 'System.Text.StringBuilder' -ArgumentList $initialCapacity
for ($i = 0; $i -lt $array.Length; $i++)
{
$resultBuilder.Append($array[$i]) | Out-Null # Suppress [StringBuilder] method returning itself
}
$result = $resultBuilder.ToString()
Just use
-join $array
which will glue all elements together.
I'm using Powershell 1.0 to remove an item from an Array. Here's my script:
param (
[string]$backupDir = $(throw "Please supply the directory to housekeep"),
[int]$maxAge = 30,
[switch]$NoRecurse,
[switch]$KeepDirectories
)
$days = $maxAge * -1
# do not delete directories with these values in the path
$exclusionList = Get-Content HousekeepBackupsExclusions.txt
if ($NoRecurse)
{
$filesToDelete = Get-ChildItem $backupDir | where-object {$_.PsIsContainer -ne $true -and $_.LastWriteTime -lt $(Get-Date).AddDays($days)}
}
else
{
$filesToDelete = Get-ChildItem $backupDir -Recurse | where-object {$_.PsIsContainer -ne $true -and $_.LastWriteTime -lt $(Get-Date).AddDays($days)}
}
foreach ($file in $filesToDelete)
{
# remove the file from the deleted list if it's an exclusion
foreach ($exclusion in $exclusionList)
{
"Testing to see if $exclusion is in " + $file.FullName
if ($file.FullName.Contains($exclusion)) {$filesToDelete.Remove($file); "FOUND ONE!"}
}
}
I realize that Get-ChildItem in powershell returns a System.Array type. I therefore get this error when trying to use the Remove method:
Method invocation failed because [System.Object[]] doesn't contain a method named 'Remove'.
What I'd like to do is convert $filesToDelete to an ArrayList and then remove items using ArrayList.Remove. Is this a good idea or should I directly manipulate $filesToDelete as a System.Array in some way?
Thanks
The best way to do this is to use Where-Object to perform the filtering and use the returned array.
You can also use #splat to pass multiple parameters to a command (new in V2). If you cannot upgrade (and you should if at all possible, then just collect the output from Get-ChildItems (only repeating that one CmdLet) and do all the filtering in common code).
The working part of your script becomes:
$moreArgs = #{}
if (-not $NoRecurse) {
$moreArgs["Recurse"] = $true
}
$filesToDelete = Get-ChildItem $BackupDir #moreArgs |
where-object {-not $_.PsIsContainer -and
$_.LastWriteTime -lt $(Get-Date).AddDays($days) -and
-not $_.FullName.Contains($exclusion)}
In PSH arrays are immutable, you cannot modify them, but it very easy to create a new one (operators like += on arrays actually create a new array and return that).
I agree with Richard, that Where-Object should be used here. However, it's harder to read.
What I would propose:
# get $filesToDelete and #exclusionList. In V2 use splatting as proposed by Richard.
$res = $filesToDelete | % {
$file = $_
$isExcluded = ($exclusionList | % { $file.FullName.Contains($_) } )
if (!$isExcluded) {
$file
}
}
#the files are in $res
Also note that generally it is not possible to iterate over a collection and change it. You would get an exception.
$a = New-Object System.Collections.ArrayList
$a.AddRange((1,2,3))
foreach($item in $a) { $a.Add($item*$item) }
An error occurred while enumerating through a collection:
At line:1 char:8
+ foreach <<<< ($item in $a) { $a.Add($item*$item) }
+ CategoryInfo : InvalidOperation: (System.Collecti...numeratorSimple:ArrayListEnumeratorSimple) [], RuntimeException
+ FullyQualifiedErrorId : BadEnumeration
This is ancient. But, I wrote these a while ago to add and remove from powershell lists using recursion. It leverages the ability of powershell to do multiple assignment . That is, you can do $a,$b,$c=#('a','b','c') to assign a b and c to their variables. Doing $a,$b=#('a','b','c') assigns 'a' to $a and #('b','c') to $b.
First is by item value. It'll remove the first occurrence.
function Remove-ItemFromList ($Item,[array]$List(throw"the item $item was not in the list"),[array]$chckd_list=#())
{
if ($list.length -lt 1 ) { throw "the item $item was not in the list" }
$check_item,$temp_list=$list
if ($check_item -eq $item )
{
$chckd_list+=$temp_list
return $chckd_list
}
else
{
$chckd_list+=$check_item
return (Remove-ItemFromList -item $item -chckd_list $chckd_list -list $temp_list )
}
}
This one removes by index. You can probably mess it up good by passing a value to count in the initial call.
function Remove-IndexFromList ([int]$Index,[array]$List,[array]$chckd_list=#(),[int]$count=0)
{
if (($list.length+$count-1) -lt $index )
{ throw "the index is out of range" }
$check_item,$temp_list=$list
if ($count -eq $index)
{
$chckd_list+=$temp_list
return $chckd_list
}
else
{
$chckd_list+=$check_item
return (Remove-IndexFromList -count ($count + 1) -index $index -chckd_list $chckd_list -list $temp_list )
}
}
This is a very old question, but the problem is still valid, but none of the answers fit my scenario, so I will suggest another solution.
I my case, I read in an xml configuration file and I want to remove an element from an array.
[xml]$content = get-content $file
$element = $content.PathToArray | Where-Object {$_.name -eq "ElementToRemove" }
$element.ParentNode.RemoveChild($element)
This is very simple and gets the job done.