主题：请教：表达式代码错误

For i As Integer = 0 To Tables("软横跨悬挂节点").Rows.Count-1
   
    If i = 0 Then
       
        Dim r As Row = Tables("软横跨悬挂节点").rows(i)
        Dim JYZL As Decimal = 0
        If r.IsNull("绝缘节点") = False
            Dim JYLX As DataRow = DataTables("绝缘节点").Find("[节点类型] = '" & r("绝缘节点") & "'")
           
            If JYLX IsNot Nothing Then
                JYZL = JYLX("单横总重")
            End If
        End If
        r("负载计算值") = JYZL
       
    End If
   
Next

2楼这样写才规范，先判断是否为空，免得花时间查表。