Invoking a Script Block

Code inside a script block can either be invoked by call operators such as „&“ or „.“, or by calling the Invoke() method.

One difference is the output when there is more than one result: call operators return a plain object array whereas Invoke() returns a collection:

$code = { Get-Process }

$result1 = & $code
$result2 = $code.Invoke()

$result1.GetType().FullName
$result2.GetType().FullName

The collection returned by Invoke() has additional methods such as RemoveAt() and Insert() that can help when you need to modify the result data and insert or remove elements efficiently.

You can achieve similar things when you manually cast a cmdlet result to an ArrayList:

 
$arrayList = [Collections.ArrayList]@(Get-Process)
 

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