Runs a batch file continuously whenever another file is changed.

watch.ps1

# watch a file changes in the current directory,
# execute all tests when a file is changed or renamed

param($BatFile)

if (($BatFile -eq $null) -or (-not (Test-Path -Path $Batfile)))
{
    "Specify bat file to run continuously."
    exit
}

$watcher = New-Object System.IO.FileSystemWatcher
$watcher.Path = Get-Location
$watcher.IncludeSubdirectories = $false
$watcher.EnableRaisingEvents = $false
$watcher.NotifyFilter = [System.IO.NotifyFilters]::LastWrite -bor [System.IO.NotifyFilters]::FileName

& $BatFile
while ($true) {
    $result = $watcher.WaitForChanged([System.IO.WatcherChangeTypes]::Changed -bor [System.IO.WatcherChangeTypes]::Renamed -bOr [System.IO.WatcherChangeTypes]::Created, 1000);
    if( $result.TimedOut ) {
        continue
    }

    "Change in $($result.Name)"
    if ($result.Name -Match ".png") {
        "Skipping"
        continue
    }

    & $BatFile
}