第二步：開發工具--查看代碼--把代碼復制進去保存就OK了
代碼如下：
Private Sub Worksheet_Change(ByVal Target As Range)
' Developed by Contextures Inc.
' www.contextures.com
Dim rngDV As Range
Dim oldVal As String
Dim newVal As String
If Target.Count > 1 Then GoTo exitHandler
On Error Resume Next
Set rngDV = Cells.SpecialCells(xlCellTypeAllValidation)
On Error GoTo exitHandler
If rngDV Is Nothing Then GoTo exitHandler
If Intersect(Target, rngDV) Is Nothing Then
'do nothing
Else
Application.EnableEvents = False
newVal = Target.Value
Application.Undo
oldVal = Target.Value
Target.Value = newVal
If Target.Column = 7 Then '這裏規定好哪壹列的數據有效性是多選的，A列是第1列，依次類推，如3就是C列，7就是G列
If oldVal = "" Then
'do nothing
Else
If newVal = "" Then
'do nothing
Else
If InStr(1, oldVal, newVal) <> 0 Then '重復選擇視同刪除
If InStr(1, oldVal, newVal) + Len(newVal) - 1 = Len(oldVal) Then '最後壹個選項重復
Target.Value = Left(oldVal, Len(oldVal) - Len(newVal) - 1)
Else
Target.Value = Replace(oldVal, newVal & ",", "") '不是最後壹個選項重復的時候處理逗號
End If
Else '不是重復選項就視同增加選項
Target.Value = oldVal & "," & newVal
' NOTE: you can use a line break,
' instead of a comma
' Target.Value = oldVal _
' & Chr(10) & newVal
End If
End If
End If
End If
End If
exitHandler:
Application.EnableEvents = True
End Sub