若用vba则如下:
Private Sub Worksheet_SelectionChange(ByVal Target As Range)
If Target.Address = "$B$2" Then
Arr = Sheets(2).Range("A1:A" & Sheets(2).Range("A65536").End(3).Row)
For I = 1 To UBound(Arr)
S = S & Arr(I, 1) & ","
Next I
S = Left(S, Len(S) - 1)
With Target.Validation
.Delete
.Add Type:=xlValidateList, Formula1:=S
End With
End If
End Sub