VBA连接选定的满足条件的单元格

我试图在VBA中编写一个函数，该函数允许我连接单元格并在元素之间添加“，”。此功能的另一方面是，我只想连接与所选范围中的第一个填充颜色和字体颜色相同的单元格。（我的电子表格在具有不同颜色和字体颜色的单元格中具有标签列表）。如果在网上找到了可以满足条件的代码，那么您会感到惊奇。但是，当我尝试添加它们时，它返回值错误。这是我的功能：

Function Concat(rng As Range) As String 
     Dim rngCell As Range
     Dim strResult As String
     Dim bcolor As Long
     Dim fcolor As Long
     bcolor = rng.Cells(1, 1).Interior.ColorIndex
     fcolor = rng.Cells(1, 1).Font.ColorIndex
     For Each rngCell In rng
         If rngCell.Value <> "" And rngCell.Interior.ColorIndex = bcolor And rngCell.Font.ColorIndex = fcolor Then
            strResult = strResult & "," & rngCell.Value
         End If
     Next rngCell
     If rngCell.Value <> "" And rngCell.Interior.ColorIndex = rng.Cells(1, 1).Interior.ColorIndex And rngCell.Font.ColorIndex = rng.Cells(1, 1).Font.ColorIndex Then
         strResult = Mid(strResult, Len(",") + 1)
     End If
     Concat = strResult
End Function

我刚接触VBA（今天下午开始），所以我添加bcolor和fcolor的原因是为了调试。实际上，我认为VBA中有些我不了解的基本知识，因为即使以下函数也不会返回任何值：

Function Concat(rng As Range) As Long 'Replace "Long" by "String" after debug is over
     Dim rngCell As Range
     Dim strResult As String
     Dim bcolor As Long
     Dim fcolor As Long
     bcolor = rng.Cells(1, 1).Interior.ColorIndex
     fcolor = rng.Cells(1, 1).Font.ColorIndex
     For Each rngCell In rng
         If rngCell.Value <> "" And rngCell.Interior.ColorIndex = bcolor And rngCell.Font.ColorIndex = fcolor Then
            strResult = strResult & "," & rngCell.Value
         End If
     Next rngCell
     If rngCell.Value <> "" And rngCell.Interior.ColorIndex = rng.Cells(1, 1).Interior.ColorIndex And rngCell.Font.ColorIndex = rng.Cells(1, 1).Font.ColorIndex Then
         strResult = Mid(strResult, Len(",") + 1)
     End If
     Concat = bcolor
End Function

确实让我感到烦恼的是，此函数在执行以下操作时不会返回单元格的颜色：

Function color1(rng As Range) As Long
    color1 = rng.Cells(1, 1).Font.ColorIndex
End Function

我知道这里有些VBA编码我不了解的基本知识。但是我不知道该怎么办。如果您发现问题出在哪里，我将更正并解释我的错误是什么。谢谢！泽维尔