Is there a native, built-in construct that automatically parses console inputs into variables using the same rules as cmdlet parameters?
For example, many cmdlets accept parameter-value pairs in the form of -parameter1 unspaced-value1 -parameter2:"spaced value2".
I want to read a string using maybe Read-Host, and then parse the string into parameter-value pairs and store them into $variables, something like int main(argv, argc), but maybe in an associative array or something similar.
Not sure if i understand exactly what you want but you are definitely describing a hashtable which can simply be defined as
@{Name="Value";AnotherName="AnotherValue"}
Or more readable
@{
Name="Value"
AnotherName="AnotherValue"
}
Both would output the following which could be assigned to a variable which could be used for splatting (more on that later)
Name Value
---- -----
Name Value
AnotherName AnotherValue
Ok, that's nice but you were looking for a way to use this adhoc with Read-Host maybe? This could be where ConvertFrom-StringData saves the day. In it's simplest form :
PS C:\Users\Cameron> $data = "Data=Awesome"
PS C:\Users\Cameron> $data | ConvertFrom-StringData
Name Value
---- -----
Data Awesome
Ok... that's great.. but what about Read-Host. Let's try that now!
PS C:\Users\Cameron> Read-Host | ConvertFrom-StringData
Something=Blah
Name Value
---- -----
Something Blah
This can get complicated if you want to do more than one key/value pair since Read-Host doesn't seem to like inserting new lines in the prompt. To cheat I use -Split and -Join. Split break up the pairs and join ends up creating a newline delimited string which ConvertFrom-StringData plays with better. Side Note There is a post that has a snippet for creating multiline input from Read-Host but this is simpler.
PS C:\Users\Cameron> ((Read-Host) -Split ";") -Join "`r`n" | ConvertFrom-StringData
Key1=Value1;Key2=Value2;Key3=Value3 <---- That is what I typed in as a response to Read-Host
Name Value
---- -----
Key1 Value1
Key2 Value2
Key3 Value3
If you are still reading lets use splatting and give an actual reason to use this logic.
PS C:\Users\Cameron> $results = ((Read-Host) -Split ";") -Join "`r`n" | ConvertFrom-StringData
Get-ChildItem @results
Filter=*.txt;Path=C:\\temp <---- That is what I typed in as a response to `Read-Host`
LastWriteTime : 10/22/2014 11:43:38 PM
Length : 653018
Name : out1.txt
....output truncated....
Note: You should notice in the path I typed in the second backslash Path=C:\\temp. The reason comes from the TechNet article for ConvertFrom-StringData
ConvertFrom-StringDatasupports escape character sequences that are allowed by conventional machine translation tools. That is, the cmdlet can interpret backslashes (\) as escape characters in the string data by using theRegex.UnescapeMethod, instead of the Windows PowerShell backtick character (`) that would normally signal the end of a line in a script. Inside the here-string, the backtick character does not work. You can also preserve a literal backslash in your results by escaping it with a preceding backslash, like this:\\. Unescaped backslash characters, such as those that are commonly used in file paths, can render as illegal escape sequences in your results.
Small Update
While the ((Read-Host) -Split ";") -Join "`r`n" | ConvertFrom-StringData works I'm sure that the following is much simpler.
(Read-Host).Replace(";","`r`n") | ConvertFrom-StringData
@{Name="Value"}