主题：错误提示，列为只读，搞不清楚问题出在哪

Button5,Click事件：

Dim r As Row = Tables("报价单").Current
Dim dnew As Row = Tables("报价单").AddNew
Dim name As String = r("订单编号") & "*"
For Each c As Col In Tables("报价单").Cols
    If c.Name = "订单编号" Then
        dnew(c.Name) = name
    ElseIf c.Name <> "_Identify" Then
        dnew(c.Name) = r(c.Name)
    End If
Next
Tables("报价单").Current("财务审核") = Nothing
Tables("报价单").Current("总经理审批") = Nothing

Dim drs As List(Of DataRow)
drs = r.DataRow.GetChildRows("报价明细")
Dim rc As DataRow
For Each dr As DataRow In drs
    rc = dr.Clone
    rc("订单编号") = name
Next

运行弹出提示：

.NET Framework 版本：2.0.50727.8669
Foxtable 版本：2018.3.3.1
错误所在事件：窗口,报价记录,Button5,Click
详细错误信息：
列“研发管理费”为只读。

关键是列“研发管理费”没有设只读