How to force implied PowerShell Format-Table to repeat headers for repeated output?

Question

I am trying to repeat *nix watch functionality as provided by johnrizzo1 here.

function Watch {
    [CmdletBinding(SupportsShouldProcess=$True,C         


        

Answer 1

Most likely this has other issues but simply changing

$cmd.invoke();

to

$cmd.invoke() | ft;

works for me

Answer 2

This will work now, but your output is forced to be piped to Format-Table so it will always be in Table format.

function Watch {
    [CmdletBinding(SupportsShouldProcess=$True,ConfirmImpact='High')]
    param (
        [Parameter(Mandatory=$False,
                   ValueFromPipeline=$True,
                   ValueFromPipelineByPropertyName=$True)]
        [int]$n = 10,

        [Parameter(Mandatory=$True,
                   ValueFromPipeline=$True,
                   ValueFromPipelineByPropertyName=$True)]
        [string]$command
    )
    process {
        $cmd = [scriptblock]::Create($command)
        While($True) {
            Clear-Host
            Write-Host "Command: " $command
            $cmd.Invoke() | Format-Table -HideTableHeaders:$false
            sleep $n
        }
    }
}

watch -n 1 '$PSVersionTable.PSVersion'