我们在工作中有时候要遇到计算某个单元格中表达式的结果,如A1中有一表达式(36.25+23.6)*3-6,现要在A2中计算出A1的结果,我们一般有好几种方法: 1.利用内部插入函数evaluate计算.注:此函数能在插入名称定义中使用,也可以在VBA代码中使用,但不能在工作表中直接调用. 2.利用VBA编写一段代码 通过eval(A1)来计算出结果,但此方法需我们加载Access库. 3.以上两种方法都有其缺陷,第1种方法有字符限制,当你的表达式超出255时,Excel会崩溃.而第2种方法必须加载Access库,如果你电脑上没有安装哪就不能用.所以我通过分析上述两种方法,编写了一个无需外挂的函数(AdvanceJS1),突破了255字符限制.并且代码没有我当初想象中那么长,呵~~请大家多多指教.此程序还可以扩展,实现计算所有内部函数的功能. Option Explicit Private ExpArray() As String Private Function CustomCalculate(x As String) ExpressionArray (x) Call RemoveSign("*", "/") Call RemoveSign("+", "-") Dim i As Variant For Each i In ExpArray If i <> "&" Then CustomCalculate = Val(i) Next i End Function Private Function ExpressionArray(Expn As String) Dim length_x As Integer Dim i As Integer Dim ExpArray_bound As Integer Dim indexp As Integer Erase ExpArray length_x = Len(Expn) ExpArray_bound = 0 indexp = 1 For i = 1 To length_x If Asc(Mid(Expn, i, 1)) >= 48 Or Asc(Mid(Expn, i, 1)) = 46 Then '数字和小数点 If indexp = 2 Then indexp = 1 ExpArray_bound = ExpArray_bound + 1 End If ReDim Preserve ExpArray(ExpArray_bound) ExpArray(ExpArray_bound) = ExpArray(ExpArray_bound) & Mid(Expn, i, 1) Else ExpArray_bound = ExpArray_bound + 1 ReDim Preserve ExpArray(ExpArray_bound) ExpArray(ExpArray_bound) = Mid(Expn, i, 1) indexp = 2 End If Next i End Function Private Function RemoveSign(Sign1 As String, Sign2 As String) Dim MarkPoint As Integer Dim LeftPoint As Integer Dim LeftVar As String Dim RightPoint As Integer Dim RightVar As String Dim Length_Array As Integer Dim i As Integer MarkPoint = 0 LeftPoint = MarkPoint RightPoint = MarkPoint Length_Array = UBound(ExpArray) For i = 0 To Length_Array If ExpArray(i) = Sign1 Or ExpArray(i) = Sign2 Then MarkPoint = i LeftPoint = MarkPoint - 1 RightPoint = MarkPoint + 1 Do While ExpArray(LeftPoint) = "&" LeftPoint = LeftPoint - 1 Loop LeftVar = ExpArray(LeftPoint) Do While ExpArray(RightPoint) = "&" RightPoint = RightPoint + 1 Loop RightVar = ExpArray(RightPoint) ExpArray(MarkPoint) = Str(Evaluate(Trim(LeftVar & ExpArray(MarkPoint) & RightVar))) ExpArray(LeftPoint) = "&" ExpArray(RightPoint) = "&" End If Next i End Function Function AdvanceJS1(x As String) '主程序入口 Dim CachBound As Integer Dim cach() As Integer Dim i As Integer Dim tmp As String Dim ExpresionTemp As String CachBound = 0 For i = 1 To Len(x) If Mid(x, i, 1) = "(" Then ReDim Preserve cach(CachBound) cach(CachBound) = i CachBound = CachBound + 1 End If If Mid(x, i, 1) = ")" Then ExpresionTemp = Mid(x, cach(CachBound - 1) + 1, i - cach(CachBound - 1) - 1) tmp = Trim(Str(CustomCalculate(ExpresionTemp))) x = Left(x, cach(CachBound - 1) - 1) & tmp & Right(x, Len(x) - i) i = cach(CachBound - 1) CachBound = CachBound - 1 ReDim Preserve cach(CachBound) End If Next i AdvanceJS1 = CustomCalculate(x) End Function
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