从自定义VBA函数（不是子函数）写入Excel工作表

Question

I would greatly appreciate your assistance in helping me write data from a custom VBA function into an excel worksheet. I have been able to write from a custom VBA subroutine but get an error whilst executing a VBA function. In the sample code, "Sub write 2" and "Sub write 3" work just fine. But "Function test 2()" generates "Value!" in its cell and write3 isn't executed.

Sub write2(r As Integer, c As Integer, d As Double)
    Dim a, b As Integer
    For a = r To r + 1
        For b = c To c + 1
            Cells(a, b).Value = d
        Next b
    Next a
End Sub

Sub write3()
    Call write2(3, 60, 0.437)
End Sub

Function test2() As Double
    Call write3
    test2 = 1#
End Function

Answer 1

As per Chip Pearson's great website :

A UDF can only return a value to the cell(s) whence it was called -- it must not modify the contents or formatting of any cell and must not modify the operating environment of Excel. If you attempt to change anything, the function will terminate immediately and return a #VALUE error to the calling cell.