Example of how to code generalized JAMS (file-is-there-or-not) PreCheck Job

TestForFile_PreCheck

# simple test-for-file(s)
param( [string] $tgtdir       = '.'                , 
       [string] $tgtfile      = '*.*'              , 
       [string] $notfoundExit = "CancelJobError"   )

$_tgtdir = $tgtdir.trimend( '\' )
$_tgt = ( $_tgtdir + '\' + $tgtfile )

write-host ( "... looking for file '" + $_tgt + "'" )

$_fileCount = ( dir $_tgt -file ).count                  # old, but infallible, way to see if something's there  

if ( $_fileCount -eq 0 )                                 # nothing found, figure out how to leave
  { $_errMsg = ( '   ... file(s) NOT found in -> ' + $_tgt )
    $_notFoundExitUpper = $notfoundExit.toupper()
    write-host $_errMsg
    write-host ( "      ... job ending with JAMS status '" + $_notfoundExitUpper + "'" )
    switch ( $_notfoundExitUupper )
      { "CANCELJOBSUCCESS"
           { $host.setshouldexit(<<JAMS.Message.CancelJobSuccess>>) }
        "CANCELJOBINFO"
           { $host.setshouldexit(<<JAMS.Message.CancelJobInfo>>) }
        "CANCELJOBWARNING"
           { $host.setshouldexit(<<JAMS.Message.CancelJobWarning>>) }
        "CANCELJOBERROR"
           { $host.setshouldexit(<<JAMS.Message.CancelJobError>>) }
        default { }
      }
  }
else { write-host ( '   ... ' + $_fileCount.tostring() + ' file(s) found in ' + $_tgt )
       dir $_tgt
       exit $host.setshouldexit( 0 )
     }