Forgive my ignorance - I am trying to write a powershell cmdlet which takes user input and builds a query uri to an API (one mandatory, 3 opts) - I have kind of got the general idea that I need to use hash tables for dictionary of query strings and parameters.

I'm trying to build $baseurl + $querystring + '=' + $parameter + '&' + $querystring + '=' $value (if not null)

e.g. https://example.com/api?param1=value¶m2=value

so far - and this is very rough, and completely not working:

            Function Get-commonURI{ #takes 4 params from user
                [CmdletBinding()]
                Param(
                    [Parameter(Mandatory=$true,
                                ValueFromPipeline=$true,
                                ValueFromPipelineByPropertyName=$true)]

                                [String[]]$value1

                                [Parameter(Mandatory=$false,
                                ValueFromPipeline=$true,
                                ValueFromPipelineByPropertyName=$true)]

                                [String[]]$value2,
                                [String[]]$value3,
                                [String[]]$value4 

                ) #end param 
            }
        #put the input into a paramter hash table with the query strings

        $Parameters = @{
            query = 'querysting1', 'querystring2', 'querystring3', 'querystring4'
            values = $value1,$value2.$value2, $value4
        }

        uri = https://example.com/api?

    $HttpValueCollection = [System.Web.HttpUtility]::ParseQueryString([String]::Empty)

    foreach ($Item in $Parameters.GetEnumerator()) {
#I want to append each query passed in on the cli

foreach ($Value in $Item.Value) {
      $ParameterName = $Item.value

      $HttpValueCollection.Add($ParameterName, $Value)}

$Request  = [System.UriBuilder]($Uri)
$Request.Query = $HttpValueCollection.ToString()

invoke-webrequest $Request.Uri

}

I have something like that written but it's not working - am I even on the right track here? - I'm sure this has been done a million times but don't even know what to google - something tells me I shouldn't set up the hash table with variables. thanks for looking.