主题：[求助]程序异常

If e.DataTable.Name <> "变更记录" Then   '数据变更记录
    Dim dr As DataRow = DataTables("变更记录").AddNew
    
    dr("表名") = e.DataTable.Name
    dr("列名") = e.DataCol.Name
    dr("行号") = e.DataRow("_Identify")
    dr("时间") = Date.Now
    dr("操作") = """" & e.OldValue &  """ 改成了 """ & e.NewValue & """"  
End If
 messagebox.show(1)
If e.DataCol.Name = "零件图号" Then   '订单零件名称,含税单价,供应商简称的来源
    Dim nms() As String = {"零件名称","A点_含税单价_更新后","A点_供应商简称"}
    If e.NewValue Is Nothing Then
        For Each nm As String In nms
            e.DataRow(nm) = Nothing
        Next
messagebox.show(2)
    Else
        Dim dr As DataRow
        dr = DataTables("价格表").Find("[零件图号] = '" & e.NewValue & "'")
        If dr IsNot Nothing
            For Each nm As String In nms
                e.DataRow(nm) = dr(nm)
            Next
        End If
    End If
End If
messagebox.show(3)
If e.DataCol.Name = "供应商简称" Then   '合同采购通则和供应商代码更新
    Dim esb() As String = {"供应商代码","合同编号_采购通则"}
    If e.NewValue Is Nothing Then
        For Each es As String In esb
            e.DataRow(es) = Nothing
        Next
    Else
messagebox.show(4)
        Dim dt As DataRow
        dt = DataTables("供应商信息表").Find("[供应商简称] = '" & e.NewValue & "'")
        If dt IsNot Nothing
            For Each es As String In esb
                e.DataRow(es) = dt(es)
            Next
        End If
    End If
End If
messagebox.show(5)

上面程序运行提示如下：