Powershell Excel PivotFilters.Add - excel

Question

I've written a Powershell script to grab a CSV, create an Excel sheet from it, and create a Pivottable with a few rows and summary values. I'm also able to add a filter field but what I cannot successfully do is tell the filter field what value I want it to filter on.
The PivotFilters.Add and PivotFilters.Add2 methods always throw a "Value does not fall within the expected range" error.
Here's the relevant portions of the code:
# Add PivotTable
$WS2 = $WBK1.Worksheets.Add()
$WS2.Name = "PivotTable"
$xlPivotTableVersion15 = 5 # Excel 2013
$xlPivotTableVersion12 = 3 # Excel 2007
$xlDescending = 2
$xlDatabase = 1 # this just means local sheet data
$xlHidden = 0
$xlRowField = 1
$xlColumnField = 2
$xlFilterField = 3
$xlDataField = 4
$xlSum = -4157
$xlAverage = -4106
$xlCount = -4112
$xlRight = -4152
$pivotRange = $WS1.UsedRange
$PivotTable = $WBK1.PivotCaches().Create($xlDatabase,$pivotRange,$xlPivotTableVersion15)
$PivotTable.CreatePivotTable("R1C1","Tables1") | Out-Null
[void]$WS2.Select()
$WBK1.ShowPivotTableFieldList = $true
# configure pivottable fields
$PivotFields = $WS2.PivotTables("Tables1").PivotFields("VmName")
$PivotFields.Orientation = $xlRowField
$PivotFields = $WS2.PivotTables("Tables1").PivotFields("RAM")
$PivotFields.Orientation = $xlDataField
$PivotFields.Function = $xlAverage
$PivotFields = $WS2.PivotTables("Tables1").PivotFields("vCPU")
$PivotFields.Orientation = $xlDataField
$PivotFields.Function = $xlAverage
$PivotFields = $WS2.PivotTables("Tables1").PivotFields("Dept") # I also tried commenting these lines out
$PivotFields.Orientation = $xlFilterField # I also tried commenting these lines out
$xlValueEquals = 7
$xlCaptionEquals = 15
$WS2.PivotTables("Tables1").PivotFields("Dept").PivotFilters.Add2($xlValueEquals, "Finance")
I have tried using both PivotFilters.Add and PivotFilters.Add2 either way I always get "Value does not fall within the expected range."
I've also tried commenting out the lines annotated above as I wondered if already having a filter created was confusing it.
Any advice greatly appreciated!

Answer 1

OK so in the end I found that basically writing a value into the cell of the filter I created using...
$PivotFields = $WS2.PivotTables("Tables1").PivotFields("Dept")
$PivotFields.Orientation = $xlFilterField
...worked and so I could do away with the PivotFilters.Add / PivotFilters.Add2 method. If anyone does know the answer to that I'm sure someone on t'interweb would be grateful for the solution being shared.

Answer 2

I too never got the PivotFilters.Add method to work. What did work for me, however, was creating and manipulating a slicer.
Once created and configured (e.g. a date slicer), you can query the slicer's SlicerCacheLevel.SlicerItems array for valid values and then apply filtering / slice the data by updating the array in SlicerCache.VisibleSlicerItemsList.
Confusingly, there is a SlicerCacheLevel.VisibleSlicerItemsList that errors when you try to update it. I didn't look into further as SlicerCache.VisibleSlicerItemsList worked.