powershell, function calls fomr an array - arrays

Question

So I am curious how to call a function from an array?
Function example:
function test($a, $b)
{
write-host $a
write-host $b
}
An array
$testArray = #{"test";"testA";"testB"}
And the whole bit I want to work is
$testArray[0] $testArray[1] $testArray[2]
Essentially mimic this
test "testA" "testB"
Reason for this is I have a few arrays like this and a loop that would go through each one using the custom function call on the data in each array.
Basically trying a different programing style.

Answer 1

Ok, it sounds like you have an array of arrays to be honest, so we'll go with that. Then let's reference this SO question which very closely resembles your question, and from that take away the whole [scriptblock]::create() thing, and splatting arrays. From that we can come up with this script:
function test($a, $b)
{
Write-Host "Function 'test'"
write-host $a
write-host $b
}
function test2($a, $b)
{
Write-Host "Function 'test2'"
write-host $b
write-host $a
}
$TestArray = #() #the correct way to create an array, instead of a broken HashTable
$testArray = #("test","testA","testB"),#("test2","testC","testD")
ForEach($Test in $TestArray){
$script = [scriptblock]::Create($test[0]+" #Args")
$script.Invoke($test[1..$test.count])
}
If all you have is one array, and not an array of arrays then I guess this is pretty simple. You could do:
$testArray = #("test","testA","testB")
$script = [scriptblock]::Create($testArray[0]+" #Args")
$script.Invoke($testArray[1..$testArray.count])
Edit (Capturing): Ok, to capture the results of a function you should be able to prefix it with $Variable = and be good to go, such as:
$MyResults = $script.Invoke($testArray[1..$testArray.count])
That will capture any output given by the function. Now, since the functions we have been working with only perform Write-Host they don't actually output anything at all, they just print text to the screen. For this I would modify the function a bit to get real output that's usable. In this example the function takes 2 parameters as input, and creates a new object with those 2 parameters assigned to it as properties. That object is the output.
function test($a, $b)
{
New-Object PSObject -Property #{Value1=$a;Value2=$b}
}
$testArray = #("test","testA","testB")
$script = [scriptblock]::Create($testArray[0]+" #Args")
$MyResults = $script.Invoke($testArray[1..$testArray.count])
Now if you ran that you would end up with the variable $MyResults being a PSCustomObject that has 2 properties named Value1 and Value2. Value1 would contain the string "testA" and Value2 would contain the string "testB". Any pair of strings passed to that function would output 1 object with 2 properties, Value1 and Value2. So after that you could call $MyResults.Value1 and it would return testA.