Question

I’m new to Powershell and I’m having an issue with the Get-Job command. In my script, I’m testing out multi-threading and am doing something like:

$Program = {
    "Thread " + $args[0];
    Start-Sleep 5;
}
Start-Job $Program -ArgumentList @($i) | Out-Null

The Start-Job call is actually in a loop in which I’m creating multiple jobs. Below this, I have:

Get-Job
"Jobs Running: " + $(Get-Job -State Running).count 

If there are multiple jobs running, I will get output like:

Id              Name            State      HasMoreData     Location             Command
--              ----            -----      -----------     --------             -------
2201            Job2201         Running    True            localhost            ...
2199            Job2199         Running    True            localhost            ...
2197            Job2197         Running    True            localhost            ...
2195            Job2195         Running    True            localhost            ...
2193            Job2193         Completed  True            localhost            ...
2191            Job2191         Completed  True            localhost            ...
2189            Job2189         Completed  True            localhost            ...
2187            Job2187         Completed  True            localhost            ...
Jobs Running: 4

But if there is only one job running, it seems that $(Get-Job -State Running).count isn’t returning anything:

Id              Name            State      HasMoreData     Location             Command
--              ----            -----      -----------     --------             -------
2207            Job2207         Running    True            localhost            ...
Jobs Running:

As you can see, there is one job running, but $(Get-Job -State Running).count doesn’t return anything. Any idea what’s happening here? To me, it looks like that if there are multiple jobs, $(Get-Job -State Running) returns a collection of jobs which has the .count property, whereas if there is only one job, it returns just that job, and doesn’t have the .count property. If this is the case (or if I’m doing something wrong), what command should I be using to get my expected result of $(Get-Job -State Running).count == 1?

Answer 1

Try using Measure-Object

$(Get-Job -State Running | Measure-Object).count