I've been messing arround with Powershell and googling various things as I go along. This one is a little hard to put into words that google woule understand. I can get the indevidual lines of a text file in powershell by indexing:
$textFile = Get-Content "myText.txt"
$textFile[0]
This would output the first line of the text file. But when I put the text file in quotes it will output all lines, even with the index
"$textFile[0]"
How can I still get only get the line I want, while wrapping the variable in quotes? If I try "$textFile"[0] it will just give me the whole file as before. The reason I'm trying to do this is because I'm trying to make that one line of the text file part of a bigger string that I can execute
$remote = "Enter-PSSession -ComputerName`", textFile[0]"
Invoke-Expression $remote
This is my way of illustrating what I'm trying to do.
You can use any of the following methods:
# Sub-expression operator
"Some Text $($textFile[0])"
# String format operator
"My Text {0}" -f $textFile[0]
# Concatenation
("Text"+$textFile[0])
Surrounding double quotes tells PowerShell to expand the string inside. Any variables within will be interpolated. Variables begin with $ and their following names can only have certain characters without requiring a special escape. [ would require an escape and since it isn't escaped, PowerShell interprets the variable name ending with the character just before the [. Therefore $textFile is interpolated, the whole file contents are converted into a string, and [0] is appended to the end of the string.
You can see details of the operators at About_Operators.
See About_Variables for how to create a variable including cases with special characters even if that doesn't directly apply here.
Related
I am trying to remove all lines of text after a single line of text "[info]" Here is an example:
Top=1266
[info]
name=tod
space=456
number=221,441,111,0
[version]
version=1
I only need the top, the other text will be replaced later on in the script. Here is all that I have tried
$Content -replace '\[Info\]*',''
Only removes the Info line and not anything past that. I have tried to loop, but I can't seem to find the line with a where object search.
What is a quick and easy way to remove all lines of code after a single line of set text?
To make the -replace operator treat it as one string, add (?s) to the pattern.
$Content -replace '(?s)\[Info\].*'
You also needed to match any character so .* works in this case. The second part is optional. Since you're replacing it with nothing you can simply omit it.
Read more about regular expression in powershell
https://learn.microsoft.com/en-us/powershell/module/microsoft.powershell.core/about/about_regular_expressions?view=powershell-7.1
and operators
https://learn.microsoft.com/en-us/powershell/module/microsoft.powershell.core/about/about_operators?view=powershell-7.1
I've read in the docs for PSReadLineOption that I can amend empty lines below the prompt to separate output from the next input. So I've tried the following.
Set-PSReadLineOption -ExtraPromptLineCount 3
As far I can tell, there's not empty lines appearing and I'm uncertain if I'm doing it wrong, if I'm imagining the result differently than intended or whatever is up with this.
I believe what you're trying to accomplish can be done in a simpler way. At the end of your output, just write a newline "`n" to stdout.
Write-Host "`n"
Sequences such as `n which use the back tick ` which is the PowerShell escape character, and a letter to make an escape sequence. These are called special characters. In the specific case of `n, it represents a newline. In the docs I linked, it lists the escape sequences that you can use within PowerShell, to implement these special characters.
I am working with Powershell. My issue is that my file path (which does not exist on a local computer) has an apostrophe in it. Powershell is seeing this as a single quote, so it is giving me the following error: The string is missing the terminator: '. I thought that I could escape the single quote using a backtick, but that gave me the same error.
The error does not occur when I am doing the first line of code, and I don't even need the backtick for that part. I can even see that the contents of the variable matches up with the file path that I am using. It is only when I am doing the invoke-expression part that it is giving me the error.
I am using https://learn.microsoft.com/en-us/powershell/module/microsoft.powershell.utility/invoke-expression?view=powershell-7, so I don't think the second line of the code is the problem.
My code is listed below:
$code = "\\example\example\John_Doe`'s_Folder\example.ps1"
invoke-expression -command $code
I have also tried wrapping the entire file path in double-quotes and single-quotes, but my program did not like that either. I can't remove the apostrophe as we have over a hundred of systems that are directing to John_Doe's_Folder.
Invoke-Expression should generally be avoided; definitely don't use it to invoke a script or external program.
In your case, simply use &, the call operator to invoke your script via the path stored in variable $code (see this answer for background information), in which case the embedded ' needs no escaping at all:
$code = "\\example\example\John_Doe's_Folder\example.ps1"
& $code
As for what you tried:
"\\example\example\John_Doe`'s_Folder\example.ps1" turns into the following verbatim string content:
\\example\example\John_Doe's_Folder\example.ps1
That is, the ` was removed by PowerShell's parsing of the "..." string literal itself, inside of which ` acts as the escape character; since escape sequence `' has no special meaning, the ` is simply removed.
For the ` to "survive", you need to escape the ` char. itself, which you can do with ``:
"\\example\example\John_Doe``'s_Folder\example.ps1"
This question was asked many times on SO and yet...
All I've seen were solutions where the input string has to be modified. Either by replacing all double quotes with single quotes or by using backticks.
But I have no control over the input string since I have no access to the source. I cannot change Hello "W"orld to Hello 'W'orld or Hello """W"""orld
What I can do is to wrap the whole string with any escaping characters. For example with single quotes around 'Hello "W"orld'. But none of thoses escaping mechanisms I tried worked. And I can change my PowerShell script
Q: How can I pass a string with double quotes to PowerShell as argument and retain the quotes?
How to reproduce
Save this
cls
write-host $args[0]
as PowerShell script echoArgs1.ps1 on your desktop.
Open a CMD window, navigate to your desktop folder and enter
powershell -file echoArgs1.ps1 "Hello "W"orld"
Current Output
Desired Output
You're using the $(CurText) macro to pass the currently selected text in Visual Studio to a PowerShell script file via an external tools definition.
Unfortunately, Visual Studio doesn't offer a way to escape double quotes in the selected text to guarantee that it is ultimately seen as-is by whatever external executable you pass it to.
(For most executables, including PowerShell, embedding literal " chars. in a "..."-enclosed argument requires escaping them as \" - see this answer for the full story.)
Due to this lack of proper escaping, PowerShell won't parse text passed as an argument to a script file (*.ps1) via the -File CLI parameter as expected if it contains literal " chars.
This is Visual Studio's shortcoming, but there is a workaround:
With just one argument being passed, inspect the raw command line via [Environment]::CommandLine, and consider everything after the *.ps1 file the argument, verbatim.
To simplify that process, pass $(CurText) without enclosing it in "..." in the external-tool definition (and make sure that it is separated from the previous token by just one space char.).
Inside of echoArgs1.ps1, use the following command to retrieve the argument verbatim:
$rawText = ([Environment]::CommandLine -split '\.ps1 ', 2)[-1]
The problem is that the command line interpreter has already removed the quotes. In other words, the quotes are already gone before the command reaches the PowerShell interpreter.
What you might try to do is: pulling the original bare command line ($MyInvocation.Line) and resolve the arguments by removing the command itself:
$FileName = [System.IO.Path]::GetFileName($MyInvocation.MyCommand.Path)
$Arguments = $MyInvocation.Line -Replace ("^.*\\" + $FileName.Replace(".", "\.") + "['"" ]\s*")
Write-Host $Arguments
Note that there are a few pitfalls with regards to the command filename in the command line:
it might contain a relative or absolute path
it might be quoted or not
Get-Content $user| Foreach-Object{
$user = $_.Split('=')
New-Variable -Name $user[0] -Value $user[1]}
Im trying to work on a script and have it split a text file into an array, splitting the file based on each new line
What should I change the "=" sign to
It depends on the exact encoding of the textfile, but [Environment]::NewLine usually does the trick.
"This is `r`na string.".Split([Environment]::NewLine)
Output:
This is
a string.
The problem with the String.Split method is that it splits on each character in the given string. Hence, if the text file has CRLF line separators, you will get empty elements.
Better solution, using the -Split operator.
"This is `r`na string." -Split "`r`n" #[Environment]::NewLine, if you prefer
You can use the String.Split method to split on CRLF and not end up with the empty elements by using the Split(String[], StringSplitOptions) method overload.
There are a couple different ways you can use this method to do it.
Option 1
$input.Split([string[]]"`r`n", [StringSplitOptions]::None)
This will split on the combined CRLF (Carriage Return and Line Feed) string represented by `r`n. The [StringSplitOptions]::None option will allow the Split method to return empty elements in the array, but there should not be any if all the lines end with a CRLF.
Option 2
$input.Split([Environment]::NewLine, [StringSplitOptions]::RemoveEmptyEntries)
This will split on either a Carriage Return or a Line Feed. So the array will end up with empty elements interspersed with the actual strings. The [StringSplitOptions]::RemoveEmptyEntries option instructs the Split method to not include empty elements.
The answers given so far consider only Windows as the running environment. If your script needs to run in a variety of environments (Linux, Mac and Windows), consider using the following snippet:
$lines = $input.Split(
#("`r`n", "`r", "`n"),
[StringSplitOptions]::None)
There is a simple and unusual way to do this.
$lines = [string[]]$input
This will split $input like:
$input.Split(#("`r`n", "`n"))
This is undocumented at least in docs for Conversions.
Beware, this will not remove empty entries.
And it doesn't work for Carriage Return (\r) line ending at least on Windows.
Experimented in Powershell 7.2.
This article also explains a lot about how it works with carriage return and line ends. https://virot.eu/powershell-and-newlines/
having some issues with additional empty lines and such i found the solution to understanding the issue. Excerpt from virot.eu:
So what makes up a new line. Here comes the tricky part, it depends.
To understand this we need to go to the line feed the character.
Line feed is the ASCII character 10. It in most programming languages
escaped by writing \n, but in powershell it is `n. But Windows is not
content with just one character, Windows also uses carriage return
which is ASCII character 13. Escaped \r. So what is the difference?
Line feed advances the pointer down one row and carriage return
returns it to the left side again. If you store a file in Windows by
default are linebreaks are stored as first a carriage return and then
a line feed (\r\n). When we aren’t using any parameters for the
split() command it will split on all white-space characters, that is
both carriage return, linefeed, tabs and a few more. This is why we
are getting 5 results when there is both carriage return and line
feeds.