Read-Host: Show how to trim leading and trailing whitespace from user input

[mklement0]

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Links

https://learn.microsoft.com/en-us/powershell/module/Microsoft.PowerShell.Utility/Read-Host?view=powershell-7.3&viewFallbackFrom=powershell-7

Summary

Typically, any leading or trailing whitespace in user input is considered incidental, and the desire is to remove it.

As an aside: The following feature request asks for a -Trim switch to support incidental whitespace removal directly.

• Read-Host : Add Trim Option PowerShell/PowerShell#19680

In the absence of direct trimming support in Read-Host (at least for now), showing an example of how to trim after the fact would be helpful; e.g.:

$userInput = (Read-Host 'Enter something').Trim()

Details

No response

Suggested Fix

No response

[sdwheeler]

I don't think this belongs in the Read-Host docs for the same reasons cited in PowerShell/PowerShell#19680 (comment). However, I think a conceptual article that covered string manipulation would be useful and more appropriate.

[mklement0]

@sdwheeler, I find the reasoning in the linked comment specious, and I will respond in detail there.

In summary, let me say: Read-Host and Write-Host are essential for building user interfaces, which has nothing to do with the automatic prompting mechanism for mandatory parameters (which is so limited as to be near useless - see PowerShell/PowerShell#4068 and PowerShell/PowerShell#7093)

As noted, wanting to remove incidental whitespace is the typical use case.

That Read-Host doesn't even support that on an opt-in basis is unfortunate, so the next best thing is to show how to do it manually, which is therefore very much appropriate for the Read-Host help topic (and is not mutually exclusive with a general string-handling conceptual topic).

[sdwheeler]

Reopening this issue. We still should create an article about string manipulation.

[sdwheeler]

Created #10289 to track new article