By default, when a PowerShell function exits, it “forgets” all internal variables. However, there is a workaround that creates persisting internal variables. Here is how:
# create a script block with internal variables # that will persist $c = & { # define an internal variable that will # PERSIST and keep its value even though # the function exits $a = 0 { # use the internal variable $script:a++ "You called me $a times!" }.GetNewClosure() }
This code creates a script block with an internal variable that keeps its value. When you run this script block multiple times, the counter increments:
PS> & $c You called me 1 times! PS> & $c You called me 2 times! PS> & $c You called me 3 times!
Yet, the variable $a inside the script block is neither global nor scriptglobal. It only exists inside the script block:
PS> $a
To turn the script block into a function, add this:
PS> Set-Item -Path function:Test-Function -Value $c PS> Test-Function You called me 5 times! PS> Test-Function You called me 6 times!
