Below is the code where I am taking server names from a text file and concatenating with comma.
But when I am printing the value, it is coming with an extra new line after the values.
I tried doing $erversToReboot.Trim(), but didn't helped.
$ServerList = Get-Content "D:\ServerName.txt"
$Servers=""
foreach($Server in $ServerList)
{
$Servers += $Server + ","
}
[string]$ServersToReboot= $Servers.TrimEnd(",")
The output coming as
server1,server2
---one extra line here---
Please let me know what is going wrong here.
Best as I can tell, you're attempting to comma separate your servers. I'd skip the Foreach construct myself and simply use the join operator.
$ServerList = Get-Content -Path 'D:\ServerName.txt'
$ServerList -join ','
This can be done in a single statement, as well.
$ServerList = (Get-Content -Path 'D:\ServerName.txt') -join ','
Tommy
As others have noted, it's in general much simpler to use the -join operator to join the input lines with a specifiable separator.
As for the problem of an extra empty line: Gert Jan Kraaijeveld plausibly suggests that your input file has an extra empty line at the end, while noting that it is actually not what would happen with the code you've posted, which should work fine (despite its inefficiency).
Perhaps the extra line is an artifact of how you're printing the resulting value.
To answer the related question of how to ignore empty lines in the input file:
Assuming that it is OK to simply remove all empty lines from the input, the simplest PowerShell-idiomatic solution is:
#(Get-Content D:\ServerName.txt) -ne '' -join ','
#(Get-Content D:\ServerName.txt) returns the input lines as an array[1] of strings, from which -ne '' then removes empty lines, and the result of which -join joins with separator ,
[1] Get-Content D:\ServerName.txt would return a scalar (single string), if the input file happened to contain only 1 line, because PowerShell generally reports a single output object as itself rather than as a single-element array when pipeline output is collected.
Because of that, #(...), the array-subexpression operator - instead of just (...) - is needed in the above command: it ensures that the output from Get-Command is treated as an array, because the -ne operator acts differently with a scalar LHS and returns a Boolean rather than filtering the LHS's elements: compare 'foo' -ne '' to #('foo') -ne ''.
By contrast, the #(...) is not necessary if you pass the result (directly) to -join (which simply is a no-op with a scalar LHS):
(Get-Content D:\ServerName.txt) -join ','
Related
I apologise for asking the very basic question as I am beginner in Scripting.
i was wondering why i am getting different result from two different source with the same formatting. Below are my sample
file1.txt
Id Name Members
122 RCP_VMWARE-DMZ-NONPROD DMZ_NPROD01_111
DMZ_NPROD01_113
123 RCP_VMWARE-DMZ-PROD DMZ_PROD01_110
DMZ_PROD01_112
124 RCP_VMWARE-DMZ-INT.r87351 DMZ_TEMPL_210.r
DMZ_DECOM_211.r
125 RCP_VMWARE-LAN-NONPROD NPROD02_20
NPROD03_21
NPROD04_22
NPROD06_24
file2.txt
Id Name Members
4 HPUX_PROD HPUX_PROD.3
HPUX_PROD.4
HPUX_PROD.5
i'm trying to display the Name column and with this code i'm able to display the file1.txt correctly.
PS C:\Share> gc file1.txt |Select-Object -skip 1 | foreach-object { $_.split(" ")[1]} | ? {$_.trim() -ne "" }
RCP_VMWARE-DMZ-NONPROD
RCP_VMWARE-DMZ-PROD
RCP_VMWARE-DMZ-INT.r87351
RCP_VMWARE-LAN-NONPROD
However with the file2 im getting a different output.
PS C:\Share> gc .\file2.txt |Select-Object -skip 1 | foreach-object { $_.split(" ")[1]} | ? {$_.trim() -ne "" }
4
changing the code to *$_.split(" ")[2]}* helps to display the output correctly
However, i would like to have just 1 code which can be apply for both situation.appreciate if you can help me to sort this.. thank you in advance...
This happens because the latter file has different format.
When examined carefully, one notices there are two spaces between 4 and HPUX_PROD strings:
Id Name Members
4 HPUX_PROD HPUX_PROD.3
^^^^
On the first file, there is a single space between number and string:
Id Name Members
122 RCP_VMWARE-DMZ-NONPROD DMZ_NPROD01_111
^^^
As how to fix the issue depends if you need to match both file formats, or if the other has simply a typing error.
The existing answers are helpful, but let me try to break it down conceptually:
.Split(" ") splits the input string by each individual space character, whereas what you're looking for is to split by runs of (one or more) spaces, given that your column values can be separated by more than one space.
For instance 'a b'.split(' ') results in 3 array elements - 'a', '', 'b' - because the empty string between the two spaces is considered an element too.
The .NET [string] type's .Split() method is based on verbatim strings or character sets and therefore doesn't allow you to express the concept of "one ore more spaces" as a split criterion, whereas PowerShell's regex-based -split operator does.
Conveniently, -split's unary form (see below) has this logic built in: it splits each input string by any nonempty run of whitespace, while also ignoring leading and trailing whitespace, which in your case obviates the need for a regex altogether.
This answer compares and contrasts the -split operator with string type's .Split() method, and makes the case for routinely using the former.
Therefore, a working solution (for both input files) is:
Get-Content .\file2.txt | Select-Object -Skip 1 |
Foreach-Object { if ($value = (-split $_)[1]) { $value } }
Note:
If the column of interest contains a value (at least one non-whitespace character), so must all preceding columns in order for the approach to work. Also, column values themselves must not have embedded whitespace (which is true for your sample input).
The if conditional both extracts the 2nd column value ((-split $_)[1]) and assigns it to a variable ($value = ), whose value then implicitly serves as a Boolean:
Any nonempty string is implicitly $true, in which case the extracted value is output in the associated block ({ $value }); conversely, an empty string results in no output.
For a general overview of PowerShell's implicit to-Boolean conversions, see this bottom section of this answer.
Since this sort-of looks like csv output with spaces as delimiter (but not quite), I think you could use ConvertFrom-Csv on this:
# read the file as string array, trim each line and filter only the lines that
# when split on 1 or more whitespace characters has more than one field
# then replace the spaces by a comma and treat it as CSV
# return the 'Name' column only
(((Get-Content -Path 'D:\Test\file1.txt').Trim() |
Where-Object { #($_ -split '\s+').Count -gt 1 }) -replace '\s+', ',' |
ConvertFrom-Csv).Name
Shorter, but because you are only after the Name column, this works too:
((Get-Content -Path 'D:\Test\file2.txt').Trim() -replace '\s+', ',' | ConvertFrom-Csv).Name -ne ''
Output for file1
RCP_VMWARE-DMZ-NONPROD
RCP_VMWARE-DMZ-PROD
RCP_VMWARE-DMZ-INT.r87351
RCP_VMWARE-LAN-NONPROD
Output for file2
HPUX_PROD
I have a PSObject which contains the following Values
AZREUS/MYVM-0.mydomain.com
AZREUS/MYVM-1.mydomain.com
I need only the VM name stored in a new PS-Object, how can I do that.
The list should return like below.
MYVM-0
MYVM-1
a simple way can be to use -replace operator:
$list = #('AZREUS/MYVM-0.mydomain.com','AZREUS/MYVM-1.mydomain.com')
$list -replace 'AZREUS/'-replace '\.mydomain\.com'
YannCha's answer is an efficient answer if your strings always begin with AZREUS/ and end with .mydomain.com. You can use a single -replace to get the desired result.
$obj = 'AZREUS/MYVM-0.mydomain.com','AZREUS/MYVM-1.mydomain.com'
$obj -replace '^AZREUS/(.*)\.mydomain\.com$','$1'
$1 represents capture group 1, which was created by the first parentheses grouping (). It contains .* contents. See Regex for regex explanation.
Taking the same approach further dynamically, you can use pattern matching. This removes all beginning characters including the first /. Then removes the first . and all characters after it.
$obj -replace '^.*/(.*?)\..*$','$1'
See Regex for regex explanation.
Note that if your object items are not strings, they will need to support being converted to strings or you will have to do that yourself before applying -replace.
Or using -match. Do them one at a time.
'AZREUS/MYVM-0.mydomain.com' -match 'AZREUS/(.*).mydomain.com' > $null; $matches[1]
MYVM-0
'AZREUS/MYVM-1.mydomain.com' -match 'AZREUS/(.*).mydomain.com' > $null; $matches[1]
MYVM-1
I have a filepath, and I'm trying to remove the last two occurrences of the / character into . and also completely remove the '{}' via Powershell to then turn that into a variable.
So, turn this:
xxx-xxx-xx\xxxxxxx\x\{xxxx-xxxxx-xxxx}\xxxxx\xxxxx
Into this:
xxx-xxx-xx\xxxxxxx\x\xxxx-xxxxx-xxxx.xxxxx.xxxxx
I've tried to get this working with the replace cmdlet, but this seems to focus more on replacing all occurrences or the first/last occurrence, which isn't my issue. Any guidance would be appreciated!
Edit:
So, I have an excel file and i'm creating a powershell script that uses a for each loop over every row, which amounts to thousands of entries. For each of those entries, I want to create a secondary variable that will take the full path, and save that path minus the last two slashes. Here's the portion of the script that i'm working on:
Foreach($script in $roboSource)
{
$logFileName = "$($script.a).txt".Replace('(?<=^[^\]+-[^\]+)-','.')
}
$script.a will output thousands of entries in this format:
xxx-xxx-xx\xxxxxxx\x{xxxx-xxxxx-xxxx}\xxxxx\xxxxx
Which is expected.
I want $logFileName to output this:
xxx-xxx-xx\xxxxxxx\x\xxxx-xxxxx-xxxx.xxxxx.xxxxx
I'm just starting to understand regex, and I believe the capture group between the parenthesis should be catching at least one of the '\', but testing attempts show no changes after adding the replace+regex.
Please let me know if I can provide more info.
Thanks!
You can do this in two fairly simply -replace operations:
Remove { and }
Replace the last two \:
$str = 'xxx-xxx-xx\xxxxxxx\x\{xxxx-xxxxx-xxxx}\xxxxx\xxxxx'
$str -replace '[{}]' -replace '\\([^\\]*)\\([^\\]*)$','.$1.$2'
The second pattern matches:
\\ # 1 literal '\'
( # open first capture group
[^\\]* # 0 or more non-'\' characters
) # close first capture group
\\ # 1 literal '\'
( # open second capture group
[^\\]* # 0 or more non-'\' characters
) # close second capture group
$ # end of string
Which we replace with the first and second capture group values, but with . before, instead of \: .$1.$2
If you're using PowerShell Core version 6.1 or newer, you can also take advantage of right-to-left -split:
($str -replace '[{}]' -split '\\',-3) -join '.'
-split '\\',-3 has the same effect as -split '\\',3, but splitting from the right rather than the left.
A 2-step approach is simplest in this case:
# Input string.
$str = 'xxx-xxx-xx\xxxxxxx\x\{xxxx-xxxxx-xxxx}\xxxxx\xxxxx'
# Get everything before the "{"
$prefix = $str -replace '\{.+'
# Get everything starting with the "{", remove "{ and "}",
# and replace "\" with "."
$suffix = $str.Substring($prefix.Length) -replace '[{}]' -replace '\\', '.'
# Output the combined result (or assign to $logFileName)
$prefix + $suffix
If you wanted to do it with a single -replace operation (with nesting), things get more complicated:
Note: This solution requires PowerShell Core (v6.1+)
$str -replace '(.+)\{(.+)\}(.+)',
{ $_.Groups[1].Value + $_.Groups[2].Value + ($_.Groups[3].Value -replace '\\', '.') }
Also see the elegant PS-Core-only -split based solution with a negative index (to split only a fixed number of tokens off the end) in Mathias R. Jessen's helpful answer.
try this
$str='xxx-xxx-xx\xxxxxxx\x\{xxxx-xxxxx-xxxx}\xxxxx\xxxxx'
#remove bracket and split for get array
$Array=$str -replace '[{}]' -split '\\'
#take all element except 2 last elements, and concat after last elems
"{0}.{1}.{2}" -f ($Array[0..($Array.Length -3)] -join '\'), $Array[-2], $Array[-1]
Just beginning with Powershell. I have a text file that contains the string "CloseYear/2019" and looking for a way to increment the "2019" to "2020". Any advice would be appreciated. Thank you.
If the question is how to update text within a file, you can do the following, which will replace specified text with more specified text. The file (t.txt) is read with Get-Content, the targeted text is updated with the String class Replace method, and the file is rewritten using Set-Content.
(Get-Content t.txt).Replace('CloseYear/2019','CloseYear/2020') | Set-Content t.txt
Additional Considerations:
General incrementing would require a object type that supports incrementing. You can isolate the numeric data using -split, increment it, and create a new, joined string. This solution assumes working with 32-bit integers but can be updated to other numeric types.
$str = 'CloseYear/2019'
-join ($str -split "(\d+)" | Foreach-Object {
if ($_ -as [int]) {
[int]$_ + 1
}
else {
$_
}
})
Putting it all together, the following would result in incrementing all complete numbers (123 as opposed to 1 and 2 and 3 individually) in a text file. Again, this can be tailored to target more specific numbers.
$contents = Get-Content t.txt -Raw # Raw to prevent an array output
-join ($contents -split "(\d+)" | Foreach-Object {
if ($_ -as [int]) {
[int]$_ + 1
}
else {
$_
}
}) | Set-Content t.txt
Explanation:
-split uses regex matching to split on the matched result resulting in an array. By default, -split removes the matched text. Creating a capture group using (), ensures the matched text displays as is and is not removed. \d+ is a regex mechanism matching a digit (\d) one or more (+) successive times.
Using the -as operator, we can test that each item in the split array can be cast to [int]. If successful, the if statement will evaluate to true, the text will be cast to [int], and the integer will be incremented by 1. If the -as operator is not successful, the pipeline object will remain as a string and just be output.
The -join operator just joins the resulting array (from the Foreach-Object) into a single string.
AdminOfThings' answer is very detailed and the correct answer.
I wanted to provide another answer for options.
Depending on what your end goal is, you might need to convert the date to a datetime object for future use.
Example:
$yearString = 'CloseYear/2019'
#convert to datetime
[datetime]$dateConvert = [datetime]::new((($yearString -split "/")[-1]),1,1)
#add year
$yearAdded = $dateConvert.AddYears(1)
#if you want to display "CloseYear" with the new date and write-host
$out = "CloseYear/{0}" -f $yearAdded.Year
Write-Host $out
This approach would allow you to use $dateConvert and $yearAdded as a datetime allowing you to accurately manipulate dates and cultures, for example.
In PS 5.0 I can split and trim a string in a single line, like this
$string = 'One, Two, Three'
$array = ($string.Split(',')).Trim()
But that fails in PS 2.0. I can of course do a foreach to trim each item, or replace ', ' with ',' before doing the split, but I wonder if there is a more elegant approach that works in all versions of PowerShell?
Failing that, the replace seems like the best approach to address all versions with a single code base.
TheMadTechnician has provided the crucial pointer in a comment on the question:
Use the -split operator, which works the same in PSv2: It expects a regular expression (regex) as the separator, allowing for more sophisticated tokenizing than the [string] type's .Split() method, which operates on literals:
PS> 'One, Two, Three' -split ',\s*' | ForEach-Object { "[$_]" }
[One]
[Two]
[Three]
Regex ,\s* splits the input string by a comma followed by zero or more (*) whitespace characters (\s).
In fact, choosing -split over .Split() is advisable in general, even in later PowerShell versions.
However, to be fully equivalent to the .Trim()-based solution in the question, trimming of leading and trailing whitespace is needed too:
PS> ' One, Two,Three ' -split ',' -replace '^\s+|\s+$' | ForEach-Object { "[$_]" }
[One]
[Two]
[Three]
-replace '^\s+|\s+$' removes the leading and trailing whitespace from each token resulting from the split: | specifies an alternation so that the subexpressions on either side of it are considered a match; ^\s+, matches leading whitespace, \s+$ matches trailing whitespace; \s+ represents a non-empty (one or more, +) run of whitespace characters; for more information about the -replace operator, see this answer.
(In PSv3+, you could simplify to (' One, Two,Three ' -split ',').Trim() or use the solution from the question.
To also weed out empty / all-whitespace elements, append -ne '')
As for why ('One, Two, Three'.Split(',')).Trim() doesn't work in PSv2: The .Split() method returns an array of tokens, and invoking the .Trim() method on that array - as opposed to its elements - isn't supported in PSv2.
In PSv3+, the .Trim() method call is implicitly "forwarded" to the elements of the resulting array, resulting in the desired trimming of the individual tokens - this feature is called member-access enumeration.
I don't have PS 2.0 but you might try something like
$string = 'One, Two, Three'
$array = ($string.Split(',') | % { $_.Trim() })
and see if that suits. This is probably less help for you but for future readers who have moved to future versions you can use the #Requires statement. See help about_Requires to determine if your platforms supports this feature.