VBA使用数组值作为单元格验证值

我现在在做什么

1. 使用来自多个工作表的特定列（项目列），用唯一数据填充数组
2. 使用上面的数组值在另一个工作表中填充一个下拉列表

但是，我在尝试设置的验证步骤上出现错误 Formula1:=arrItems()

这是我的代码：

    Dim ws As Worksheet
    Dim tmpItems As String
    Dim arrItems() As String
    Dim tmpDates As String
    Dim arrDates() As String
    Dim ItemColumn As Range
    Const ItemHeaderCell As String = "Item"
    Dim EmptyRange As Range

    For Each ws In ActiveWorkbook.Worksheets
      If ws.Name <> "Raw Data" Then
        ws.ListObjects.Add(xlSrcRange, ws.UsedRange, , xlYes).Name = ws.Name
        ws.ListObjects(ws.Name).TableStyle = "TableStyleMedium9"
        tmpDates = tmpDates & ws.Name & "|"
        Set ItemColumn = ws.UsedRange.Find(ItemHeaderCell, , xlValues, xlWhole)

        For Each EmptyRange In Intersect(ItemColumn.EntireColumn, ws.UsedRange).Cells
        'skip the header and empty cells
          If Not IsEmpty(EmptyRange.Value) And EmptyRange.Address <> ItemColumn.Address 
        And (InStr(tmpItems, EmptyRange) = 0) Then
            tmpItems = tmpItems & EmptyRange.Value & "|"
          End If
        Next EmptyRange
      End If
    Next ws

    If Len(tmpItems) > 0 Then 
       tmpItems = Left(tmpItems, Len(tmpItems) - 1)
       arrItems = Split(tmpItems, "|")

       If Len(tmpDates) > 0 Then 
         tmpDates = Left(tmpDates, Len(tmpDates) - 1)
         arrDates = Split(tmpDates, "|")

         Dim worksheet2 As Worksheet
         Set worksheet2 = ActiveWorkbook.Sheets.Add(Before:=ActiveWorkbook.Sheets(1))
         worksheet2.Name = "Main"

         With worksheet2.Range("A1").Validation
            .Delete
            .Add Type:=xlValidateList, AlertStyle:=xlValidAlertStop, Operator:=xlBetween, Formula1:=arrItems()
         End With

如何纠正此错误？