How to read specific variables from the string using PowerShell?

Question

There is a file which has this content

   SomeText1

   SomeCommand -parameterName abc -login def -password geh

   SomeText2

Could you please advise what PowerShell should be in order to read into the array the variables and values (may be like key/value pair) for

 login=def
 password=geh

The specific about that question is that the order of the login and password parameters may be different, so I need to find the way how to locate the key/value based on the known key name. Also, I know that I need only login and password parameters and associated values.

Thank you very much for your help, in advance!

P.S. I was planning to use the following commands to read the file content, but that can be changed:

$GetFileName = "$env:userprofile\Desktop\Folder\Input.txt" 

$content = [IO.File]::ReadAllText($GetFileName)

mklement0 · Accepted Answer · 2018-11-02 03:27:20Z

The Select-String cmdlet offers a convenient way to use regular expressions to extract information from files:

$inputFile = "$env:userprofile\Desktop\Folder\Input.txt"

# Extract the information of interest and output it as a hashtable.
# Use $ht = Select-String ... to capture the hashtable in a variable.
Select-String -Allmatches '(?<=-(login|password) +)[^ ]+' $inputFile |
  ForEach-Object {
    foreach ($match in $_.Matches) {
      @{ $match.Groups[1] = $match.Value }
    }
  }

With the sample input, the output is a single hashtable (if multiple lines match, you'll get a hashtable for each line):

Name                           Value
----                           -----
login                          def
password                       geh

-AllMatches tells Select-String to search for multiple matches on each line.
Regex '(?<=-(login|password) +)[^ ]+' captures the argument associated with parameters -login and -password, while capturing the parameter name in a capture group.
- Note that the regex assumes that the argument values have no embedded spaces, but that is usually a safe assumption in usernames and passwords.
foreach ($match in $_.Matches) processes each match, and constructs and outputs a hashtable (@{ ... } ) whose key is the captured parameter name, and whose value is the captured argument.

boxdog · Accepted Answer · 2018-11-02 00:11:35Z

You can use regular expressions to do this. For examle, here is how you can pull the parameters and arguments from a command string and output them as a custom object (for easy manipulation later):

$cmd = "Some-Command -ParameterOne abc -ParameterTwo def -ParameterThree geh -SwitchParameter"

[Regex]::Matches($cmd, "-(?<param>\w+) (?<arg>\w*)|-(?<param>\w+)") |
    ForEach-Object {
        [PsCustomObject]@{
            Parameter = $_.Groups['param'].Value
            Argument = $_.Groups['arg'].Value
        }
    }

The output is like this:

Parameter       Argument
---------       --------
ParameterOne    abc     
ParameterTwo    def     
ParameterThree  geh     
SwitchParameter

Something like Get-Content might be suitable for reading the command from the file in the first place.

Collectives™ on Stack Overflow

How to read specific variables from the string using PowerShell?

2 Answers 2

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related