re: Expert Solution for 2011 Scripting Games Beginner Event 7: Use PowerShell to Get the Number of Days Between Dates

jrussell97 — Tue, 26 Apr 2011 15:35:53 GMT

I can see that many people used the -f switch to format the output. My question is how they discovered the switch. I have looked at the help for write-host and I do not see that anywhere. Perhaps an article about finding help would clear things up for me.

Thanks

re: Expert Solution for 2011 Scripting Games Beginner Event 7: Use PowerShell to Get the Number of Days Between Dates

cseiter — Tue, 26 Apr 2011 12:58:48 GMT

Yeah, but what happens when it ends up only being 1 day? I think mine was the only one that corrected for grammar with it changing the noun and verb to "There is 1 day left" instead of the usual "There are 1 days left". Your one-liner is much more elegant than mine. I saw the subtract but didn't investigate any farther on it to find the timespan.

re: Expert Solution for 2011 Scripting Games Beginner Event 7: Use PowerShell to Get the Number of Days Between Dates

Klaus Schulte — Tue, 26 Apr 2011 10:48:46 GMT

Hello Michael,

I probably could have written in german :-)

Well, as everybody might know in between, I should rename to Mr.Ed ... oh, no! This one's already taken ... Mr.Error :-)

And really I just copied the solution and saved it to disk and called it, like you proposed:

PS F:\Users\Klaus\SG2011> ./expert_be7.ps1 –EndDate 7/31/11 –MileStone "the end of the fiscal year"

Get-Date : Der Parameter "Date" kann nicht gebunden werden. Der Wert "7/31/11" kann nicht in den Typ "System.DateTime" konvertiert wer

den. Fehler: "Die Zeichenfolge wurde nicht als gültiges DateTime erkannt."

The judges might have said: This is not a working solution ... no stars!

Of course, the solution does work in the USA and other countries using american date formats!

So nobody might have seen anything bad in it.

I really tried to make my solution work with any date format and used the approach to pass strings in

and try to convert them to localized DateTime values, like that:

if (!($firstDate = $firstDay -as [DateTime]))

{

return "can't convert firstDay: '$firstDay' to a DateTime"

}

This works like charm, but it might have even been better to allow DateTimes to be passed as parameter, too!

Well besides the localization problem the solution doesn't provide any error handling and I know, that the first

thing that our users would enter into the pretty new function might be something like:

./expert_be7.ps1 –EndDate Friday –MileStone "WOW! Only few days til the end of this week!"

which will produce the same error as above of course!

Another nice feature might have been to provide an additional parameter: -StartDate that could be used to

provide an alternative to today's date at nearly no cost!

BUT: The worst aspect of the solution is, in my opinion, the fact that you do provide default values but these values

will cause the same error as above on themselves!

Param([String] $EndDate = "EndDate", [String] $MileStone = "MileStone")

Setting $EndDate to a default of "EndDate" is really a bad idea! You might have used "12/31/2011" or any other

reasonable default but not the string "EndDate"!

Providing default values that will raise errors is really a "no go" imho.

kind regards, Klaus