Ошибки и исключения

$result = & { try { Get-Item .\missing -ErrorAction Stop } catch { "caught" } }
$resultType = if($null -eq $result){'<null>'}else{$result.GetType().FullName}
[pscustomobject]@{ Result=$result; Type=$resultType; Count=@($result).Count }

$e=$null
Get-Item .\missing -ErrorAction SilentlyContinue -ErrorVariable e
$e.Count

& { $old=$ErrorActionPreference; try{$ErrorActionPreference="Stop"} finally{$ErrorActionPreference=$old} }

try { [IO.File]::ReadAllText("missing.txt") } catch [IO.FileNotFoundException] { "not found" } catch { "other" }

$result = & { try { throw [InvalidOperationException]"bad state" } catch { $_.Exception.GetType().Name } }
$items = @($result)
[pscustomobject]@{ Count=$items.Count; First=$items | Select-Object -First 1; IsNull=($null -eq $result) }

$s=$null
try{$s=[IO.MemoryStream]::new(); throw "x"}finally{if($s){$s.Dispose()}}

$Error.Clear()
Get-Item .\missing -ErrorAction SilentlyContinue
$Error[0].FullyQualifiedErrorId

$before=$Error.Count
$valueType = if($null -eq $before){'<null>'}else{$before.GetType().FullName}
[pscustomobject]@{ Value=$before; Type=$valueType; Count=@($before).Count }

$result = & { try { throw "boom" } catch { "seen"; throw } }
$summary = [ordered]@{ IsNull=($null -eq $result); Count=@($result).Count }
if($null -ne $result){$summary.Type=$result.GetType().FullName};[pscustomobject]$summary

$result = & { try { Write-Error "bad" -ErrorAction Stop } catch { $_.FullyQualifiedErrorId } }
$shape = if($null -eq $result){'<null>'}elseif($result -is [array]){'array'}else{$result.GetType().Name}
[pscustomobject]@{ Shape=$shape; Values=@($result) }