使用ISE或Powershell.exe时的字符串长度不同

Question

I have written a small user Interface with PowerShell in order to create checksums comfortable. At the moment I see a difference between using the ISE and the powershell itself.

When running the PowerShell script within the ISE I get perfect results. This is the code I am using (Just a snippet):

$aaa = (Get-FileHash -Algorithm SHA512 -Path $str_filepath |
       Select-Object -Property hash |
       Format-Table -HideTableHeaders |
       Out-string).TrimEnd().TrimStart()

So I create a checksum (SHA512) from a file. These are the results for one file as example:

Running the script in ISE:

0518E6DF62AB7B8D7A238039262C7A0E9F1F457D514EDE2BB8B3F4719340EF4B61053EC85ED30D07688B447DBC756F3A7455D7E0C84C7BCF62A8884E4715C8A0

Running the script in PowerShell:

0518E6DF62AB7B8D7A238039262C7A0E9F1F457D514EDE2BB8B3F4719340EF4B61053EC85ED30D07688B447DBC756F3A7455D7E0C84C7BCF62A8...

As you can see the string is shortend when using PowerShell. More confusing is that the shortening is not consistent. At home on my Windows 7 machine the string is even shorter then on my Windows 8.1 System at work. I know that there are some differences between ISE and PowerShell when running scripts regarding to styles. But shorter strings... Hmm.

So now the question. Does anyone of you have expierenced that difference between ISE and Powershell regarding to String length limitations? And if so. Does have anyone an answer for me how I can script it that there will be no different string results?

Answer 1

Do not use Format-* cmdlets if you need to process your data further. Those cmdlets are only for displaying data to a user. Instead expand the Hash property of the object Get-FileHash returns, either like this:

$str_checksum_sha512 = (Get-FileHash -Algorithm SHA512 -Path $str_filepath).Hash

or like this:

$str_checksum_sha512 = Get-FileHash -Algorithm SHA512 -Path $str_filepath |
                       Select-Object -Expand Hash