※ 引述《fumizuki (小獅子)》之銘言： : Public Function Eval(s As String) : '解開方程式的值 : Dim p As Integer, f As Integer, op1 As String, op2 As String : Dim a As String, o As String : '第一次進入函式，把空白全去除掉。 : Static c As Integer: c = c + 1 : If c = 1 Then s = Replace(s, " ", "") : '加法運算 : o = "+": GoSub SearchProc : If p > 0 Then GoSub SplitProc: Eval = Eval(op1) + Eval(op2): GoTo EndProc : '減法運算 : o = "-": GoSub SearchProc : If p > 0 Then GoSub SplitProc: Eval = Eval(op1) - Eval(op2): GoTo EndProc : '乘法運算 : o = "*": GoSub SearchProc : If p > 0 Then GoSub SplitProc: Eval = Eval(op1) * Eval(op2): GoTo EndProc : '除法運算 : o = "/": GoSub SearchProc : If p > 0 Then GoSub SplitProc: Eval = Eval(op1) / Eval(op2): GoTo EndProc : '指數運算 : o = "^": GoSub SearchProc : If p > 0 Then : GoSub SplitProc : If op1 Like "-*" Then : Eval = -Eval(Mid(op1, 2)) ^ Eval(op2) : Else : Eval = Eval(op1) ^ Eval(op2) : End If : GoTo EndProc : End If : Eval = Val(s) : EndProc: : c = c - 1: Exit Function : SearchProc: : p = Len(s) + 1 : Do : p = InStrRev(s, o, p - 1) 為什麼我把下面的a放到這裡就執行錯誤了?? = = a = Mid(s, p - 1, 1) : If o = "^" Then Exit Do : If p <= 1 Then : f = 0 '首字忽略；找不到則離開迴圈 : Else : a = Mid(s, p - 1, 1) : If a = "+" Or a = "-" Or a = "*" Or a = "/" Or a = "^" Then : f = 1 : Else : f = 0 : End If : End If : Loop While f = 1 : If p = 1 Then p = 0 : Return : SplitProc: : op1 = Left(s, p - 1): op2 = Mid(s, p + 1): Return : End Function -- 少年讀書，如隙中窺月； 中年讀書，如庭中望月； 老年讀書，如臺上玩月。 --

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