For some reason my script is not catching the exception when I run the following script against a file that does not exist. I based this code from examples I found on the web but it doesn't seem to work for me.
I would appreciate any tips or pointers on how to fix this.
Note: in the example below I've also tried
trap [Exception] {
but that didn't work either.
Here's the script:
function CheckFile($f) {
trap {
write-host "file not found, skipping".
continue
}
$modtime = (Get-ItemProperty $f).LastWriteTime
write-host "if file not found then shouldn't see this"
}
write-host "checking a file that does not exist"
CheckFile("C:\NotAFile")
write-host "done."
output:
PS > .\testexception.ps1
checking a file that does not exist
Get-ItemProperty : Cannot find path 'C:\NotAFile' because it does not exist.
At C:\Users\dleclair\Doc开发者_C百科uments\Visual Studio 2010\lib\testexception.ps1:12 char:35
+ $modtime = (Get-ItemProperty <<<< $f).LastWriteTime
+ CategoryInfo : ObjectNotFound: (C:\NotAFile:String) [Get-ItemProperty], ItemNotFoundException
+ FullyQualifiedErrorId : PathNotFound,Microsoft.PowerShell.Commands.GetItemPropertyCommand
if file not found then shouldn't see this
done.
PS >
Try like this:
trap { write-host "file not found, skipping";continue;}
$modtime = Get-ItemProperty c:\manoj -erroraction stop
Based on comments from OP:
I think you misunderstood what is being said in the article you have linked to:
In this example, we used continue to caused execution to return to the scope the trap is in and execute the next command. It’s important to note that execution only returns to the scope of the trap, so if the exception was thrown inside a function, or even inside a if statement, and trapped outside of it … the continue will pick up at the end of the nested scope.
So if you do something like this:
trap{ write-host $_; continue;}
throw "blah"
write-host after
after
will be printed.
But if you do something like this:
trap{ write-host $_ ; continue}
function fun($f) {
throw "blah"
write-host after
}
fun
write-host "outside after"
after
will NOT be printed, but outside after
will be.
Alternatively, use a try-catch block:
try{
$modtime = (Get-ItemProperty $f -erroraction stop).LastWriteTime
write-host "if file not found then shouldn't see this"
}
catch{
write-host "file not found, skipping".
}
You have to set $ErrorActionPreference
to SilentlyContinue
inside of the function or outside of the script (for global application) for trap
to work. Alternatively (as mentioned above), set -ErrorAction
common parameter to the same thing.
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