How to alternate actions on variables in an array (one of two things for every other variable)-CodePudding

I've been tasked with creating an API script in Powershell that will reach out for a record, change one parameter to either A or B (alternating), write the record back, then move to the next record. The part I can't get my caffeine-deprived brain around is how to perform the alternation. It basically just needs to go back and forth so approximately 50% get A and 50% get B. Any thoughts on how to accomplish this? I feel this should be simple, but I'm just not able to figure it out at the moment.

$APIURL = "https://$Server.$ServerDomain/api/v1"
$EndpointURL = $APIURL "/computer/?q=deleted:false"
$EndpointList = Invoke-RestMethod -Uri $EndpointURL -Method Get -Header @{"X-Auth-Token" = $apiKey}

# Set the new policy ID to use A on the first variable, then B on the next, then back to A, and so on
#$NewPolicyId = A
#$NewPolicyId = B

# Format the change and send it back to the server for writing
$SpecificEndpoint.policyId = $NewPolicyId
$POST_URL = "$APIURL/computer/"   $SpecificEndpoint.id
$json = $SpecificEndpoint | ConvertTo-Json
Invoke-RestMethod -Uri $POST_URL -Method Post -Header @{"X-Auth-Token" = $apiKey} -Body $json -ContentType "application/json"```

CodePudding user response：

All you need is a simple 2-item array containing the policy names, and a variable to keep track of what you picked last time:

$policies = @('A', 'B')
$pickSecond = $false

foreach($SpecificEndpoint in $EndpointList)
{
    # pick policy
    $policy = $policies[$pickSecond]
    # toggle `pickSecond` for next time
    $pickSecond = -not $pickSecond

    $SpecificEndpoint.policyId = $policy
    # ... perform API call
}

PowerShell will automatically convert $false to 0 and $true to 1 and the $policy expression thus alternates between $policies[0] and $policies[1]