Inserting for loop's variable into another variable names

Question

I'm trying to simplify a Windows interface script that my colleague did in which he used a lot of if-loops which I think can be further shortened using for-loops.

Basically we have a couple sets of computers that ranged from 4 - 12 per set & we provide each admin an interface to revert their respective snapshots.

I'm looking to replace the number in each variable with the $i value from the for-loop.

I've tried using arrays & hashtables but based on what I've gathered, they're much more suitable in storing values & not formulas that included other variables.

if($ComputerNumber -eq 4) {
   $checkBoxComputer1LocX = $leftMargin
   $checkBoxComputer1LocY = [int]$labelSubHeaderLocY + [int]$buttonHeight + [int]$padding

   $checkBoxComputer2LocX = $leftMargin
   $checkBoxComputer2LocY = [int]$labelSubHeaderLocY + [int]$buttonHeight + [int]$padding + (1 * ([int]$checkBoxHeight + [int]$padding))

   $checkBoxComputer3LocX = $leftMargin
   $checkBoxComputer3LocY = [int]$labelSubHeaderLocY + [int]$buttonHeight + [int]$padding + (2 * ([int]$checkBoxHeight + [int]$padding))

   $checkBoxComputer4LocX = $leftMargin
   $checkBoxComputer4LocY = [int]$labelSubHeaderLocY + [int]$buttonHeight + [int]$padding + (3 * ([int]$checkBoxHeight + [int]$padding))
}

This is what I'm trying to achieve:

for($i=1; $i -le $ComputerNumber; i++) {
   $checkBoxComputer$iLocX = $leftMargin
   $checkBOxComputer$iLocY = [int]$labelSubHeaderLocY + [int]$buttonHeight + [int]$padding + (($i - 0) * ([int]$checkBoxHeight + [int]padding))
}

Answer 1

To use variable indirection (referring to a variable via its name stored in another variable) for assignment, use Set-Variable (for retrieval, you'd use Get-Variable):

for($i=1; $i -le $ComputerNumber; i++) {
  Set-Variable -Name checkBoxComputer${i}LocX -Value $leftMargin
  Set-Variable -Name checkBoxComputer${i}LocY -Value ([int]$labelSubHeaderLocY + [int]$buttonHeight + [int]$padding + (($i - 0) * ([int]$checkBoxHeight + [int]padding)))
}

Note how the name of variable $i is enclosed in {...} (${i}) in order to unambiguously delineate it, so that the subsequent characters aren't considered part of the name.

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However, you can definitely use arrays and custom objects instead of individual variables, which is preferable:

[array] $checkBoxes = for($i=1; $i -le $ComputerNumber; i++) {
  [pscustomobject] @{ 
     LocX = $leftMargin
     LocY= [int]$labelSubHeaderLocY + [int]$buttonHeight + [int]$padding + (($i - 0) * ([int]$checkBoxHeight + [int]padding))
  }
}

The above creates a (0-index-based) array of custom objects that each have a .LocX and .LocY property, so that, for instance, you can access the first checkbox's .LocX value as follows:

$checkBoxes[0].LocX