Excel中保留有效数字的问题

在工作表界面中按 <alt>+<F11>,
进入代码页面，然后再 WORKBOOK中插入模块，把以下代码COPY入模块中。
就可以在工作表中使用 =YXSZ(数值，保留位数）。

如：
A1=456.789
B1=YXSZ(A1,4）
  =456.8

代码如下：

Public Function YXSZ(X, n As Integer)  'n为有效数字位数

    Dim jk, j

    Dim Y As Single

    Dim temp As String

    Dim zfh As Integer

    zfh =

    If X = "" Or (Not Application.WorksheetFunction.IsNumber(X)) Then mYX = "?Value!": Exit Function

    X = Val(X)

    If n <  Then mYX = X: Exit Function

    If X <=  Then

        zfh = -

        X = X * zfh

    End If

    If X <  Then

        j =

        Do

            temp = CStr(X)

            j = j +

        Loop Until Val(Mid$(temp, j, )) >

        j = j + n

        X = X *  ^ j

        jk = Len(CStr(Int(X))) - n

        Y = X /  ^ jk + 0.5

        YXSZ = Int(Y) *  ^ jk /  ^ j* zfh

        X = X /  ^ j

    Else

        jk = Len(CStr(Int(X))) - n

        Y = X /  ^ jk + 0.5

        YXSZ = Int(Y) *  ^ jk * zfh

    End If

End Function