已成功了，列的类型可以是文本

自定义eval3函数，可以成功仿EXCEL功能

调用：在DRAWCELL中调用

具体：

Dim s As String = e.Row(e.col.Name)
If s.StartsWith("=") Then
    e.Text = Functions.Execute("Eval3",s,e.Row)
End If

 

Dim s As String = args(0)
Dim r As Row = args(1)
\'判断是否是表达式,不是表达式,转换为数值返回
If s.StartsWith("=") = False Then
    Return s
Else
    s = s.TrimStart("=")
   
    If IsNumeric(s) Then \'如果是单个数字,直接返回
        Return Val(s)
    End If
    \'扫描表达式里的 [列名]
    Dim strCols As String = Nothing
    For Each c As Col In r.Table.Cols
        If s.Contains("[" & c.Name & "]") Then
            strCols &= "[" & c.Name & "]|"
        End If
    Next
   
    If strCols Is Nothing Then  \'不存在[列名],但是个表达式,返回
        Return eval2(s,r)
    Else  \'存在[列名]
        strCols = strCols.TrimEnd("|")
        Dim saCols() As String = strCols.Split("|")
       
        Dim sCol As String = Nothing
        Dim sValue As String = Nothing
        For j As Integer = 0 To saCols.Length - 1
            sCol = saCols(j)
            sCol = sCol.TrimStart("[")
            sCol = sCol.TrimEnd("]")
           
            sValue = Functions.Execute("Eval3",r(sCol),r)
            s = s.Replace(saCols(j),sValue)

        Next
       
        Return eval2(s,r)
    End If
End If